Now that I've considered it a bit more I would say that for regular hermetic magic I'd say this would take a ritual effect. It takes a season to perform a binding. Goetic sorcery has its own, specific and tailored, effects to work within itself... but for regular hermetic magic to counteract an effect that requires a season invested in it... should take a ritual spell at least.
Something like the 'disenchant' ritual for destroying items, but designed vs. a goetic binding.
I would entirely agree with this.
Chris
I agree about the need for a ritual spell or the use of the "begone" Commanding command. I disgree that a tailored spell would always be necessary, however. I think a higher level "disenchant" type spell would suffice. Goetic magic is already integrated into Hermetic magic to a rather high degree, after all.
I would agree if the issue were to recover fertility while the LR is in effect. I am absolutely not convinced that the issue would be so much a big deal after the LR has expired and the mage is using a different way to ensure its logevnity.
IIRC, the Wizard's grimoire quoted a LR variant that allowed the magus fertility in the equinoxes and solstices while the LR was in force. In 5th ed. terms, it would be a minor breakthrough.
Again, most likely the issue covered there is to restore fertility while the LR is in effect, and I agree that normal fertility magic may have trouble doing that.
I would side with there being a permanent loss of fertility, but it's just my opinion. The longevity ritual does not entirely end when it fails. There are two things: the anchor and the focus. The way I like to see it is that the fertility is placed into the anchor, akin to how fertility is placed into a fertility fetish. The focus connects the anchor to the magus. It is the focus that is broken when the ritual fails. You only need to recreate the focus. The anchor is still there.
Chris
But even for hermetic magic the spell must be tailored. (Don't have my books at work to confirm.) You must use a different ritual to break a familiar bond than you use to disenchant an enchanted device.
I think there's just a question of how much tailoring everyone is talking about. I would think a ritual that breaks free a bound spirit would work on everything from Goetic Arts' Binding as well as from thing in TMRE that bind spirits to spells and the like. I might even allow it to break a familiar bond if the bond is with a spirit.
Chris
I may find it reasonable that the fertility loss is permanent short of healing magic, but not for the reason you mention. As I explained upthread, there is no anchor and focus as separate parts of the ritual, they are just different names for different aspects of the same process, there is nothing in the RAW that implies or justifies their separate nature, the focus is just like swallowing a drug and the anchor is just like the drug in the body. It is also quite unreasonable to assume that part of the ritual lingers when it fails, this completely at odds with how ArM magic works, when it fails it is completely gone, short of some specific and explitely mentioned exceptions. Fertility may (or may not) remain lost when the ritual fails as a permanent side-effect, similar to a permanent injury.
I would find this kind of tailoring reasonable. Not a specific spell to undo Goetic Binding, however.
No, sorry, you are incorrect. The book specifically lists them as separate parts. The book says you create the anchor. You then perform a final (focus) ritual. Only that final ritual needs to be repeated when it ends if you want to reactivate it. Notice that initially the anchor comes prior to the focus ritual. Your analogy is flawed.
Chris
You mean, short of the sorcerer's destruction? Well, how about the spirit's destruction? That's probably easier than destroying the binding, since it's non-Hermetic magic and so probably requires a custom effect designed by someone who is more than passingly familiar with it.
I agree that they can't be used concurrently, though generally I figure this means the character stops using the Parma altogether once his Might Score is high enough, since characters can't "turn off" inherent Magic Resistance.
Interesting that you don't ask about Ablating. I guess that's because Ablating specifies, right? It would make sense that Might gained this way is Infernal Might, because magic and faerie effects have a really hard time giving characters Might. The Infernal gives out Might like candy. If you're getting a Might Score with an Infernal power, I think it should be Infernal Might. Maybe using the power taints the non-Infernal Might and makes it Infernal?
I would say no, though if the character initiated that Virtue he would gain them. It basically lets him treat the spirit like a normal animal as far as bonding with it.
I'd say it's more that what the sorcerer is doing is a subset of Rego, clearly within its purview. Almost as if the Goetic Arts and the Art of Rego have the same origins, or perhaps were integrated into Hermetic Magic when Bonisagus invented Magic Theory... 
Regarding using Vim in place of Area Lore, I think I'd rule no. Vim applies to summoning a specific spirit, but it doesn't let you call spirits to you. You need Area Lore to know what kind of spirits live in that area and how to make them show themselves to you.
The services Commanding allows are special, because you're using an infernal power to facilitate them. So I wouldn't let standard Summoning do that, not if the spirit doesn't already have the power to do that.
The sorts of services Summoning gets you are the sorts of things that spirits can do anyway. It's basically the Perform for me ("Dance, monkey, dance!") command. You're just getting them to do them for you. Like plowing your fields, or bringing you a drink of water, or stealing gold from a shop, or teaching you a language it knows. If they have powers, you could convince them to use them on your behalf, bless you or curse your enemies. Maybe fight on your side in a battle, that kind of thing.
The spirit's destruction seems like means only slightly less extreme and unacceptable in many cases to me (such as when the relationship between magus and bound spirit has been at least partially amicable and cooperative). I would want for means of destroying the binding that harm neither the magus nor the spirit. From previous discussion, this may include either Commanding, or a custom spell, which however just needs to be targeted on destroying spirit bindings in general (in addition to the goetic ones, they also exist spirit magic mysteries), and not necessarily the goetic ones specifically.
This statement is in contradiction with the RAW from TMRE and RoP:M when it is stated that characters who can potentially use either the Parma + Form or Supernatural Might MR can choose which kind to use. Therefore, such characters can "turn off" Might MR.
Ablating is a wholly different issue since it slices off chunks of raw spiritual essence and it attaches them to the mage. Since the power is Infernal (and the wickedest Goetic one to boot), it stands to reason that the Might bestowed is Infernal. Binding is a wholly different thing, it is a symbiotic relationship with a whole spirit. While the binding itself is Infernal, the spirit's nature is unchanged, including its Realm affiliation. Therefore, the Might should have the affiliation of the spirit, with an Infernal effect on top. Rewriting the whole Realm affiliation of the spirit seems really excessive.
Good luck. I imagine inventing spells to do that would be great fuel for a research project involving a magical version of Binding, which it sounds like you'd really like.
I'd agree on the custom spell if you're using the guideline that targets effects up to half the spell level. What about the spirit's Magic Resistance, wouldn't you have to penetrate it? It's possible that destroying the binding could harm the spirit, the same way it hurts a familiar when you break the bond, so wouldn't the spirit have a chance to resist?
I disagree. If that's from something I wrote, I'm sure I meant that you can use your Parma or you can lower it (or just not cast it) if you would prefer to use your Might, but you can't stack them and your Form bonuses don't add to your Might-based Resistance. It's my understanding that characters with inherent Magic Resistance can't shut it off. I mean, how could they?
I tried to convey that they're all wicked, Binding and Commanding just as much as Ablating. The character is forming a bond with an unclean spirit, essentially enslaving it to his will. They are all three evil powers that stain the soul when he uses them.
I wouldn't call it symbiotic... I don't think the Infernal does symbiotic unless as part of a lie to draw a person into sin. But let's consider this: say a sorcerer captures the spiritual manifestation of a saint and binds it to him with his infernal power. Would this give him Divine Might? My opinion, I don't think it should. It should give him Infernal Might, which is taken with supernatural force from the spirit with Divine Might and twisted to the sorcerer's ends. Likewise if he binds a magical representation of a person's mind at the moment of his death, or a faerie born of a person's reflection, I figure he is basically enslaving these beings, and his power should be appropriate to the realm that grants it to him.
Perhaps the being is tainted by the infernal power, so that while it is under the sorcerer's power, it is considered a demon even if its Might is still affiliated with another realm? Or, maybe the Might is filtered through the character's Binding or Commanding power to become infernal as the character receives it?
A magical version of Binding and Commanding, yup, since I find it rather unfair that using them on magical or faerie spirits would be so wicked as to deserve the Infernal-only level of taint.
Yup.
Only if the spirit actively resists the destruction of the bond. Otherwise, the magus is just casting a spell on oneself.
It is possible but not terribly likely IMO, however, if the spirit did want the binding in the first place, he would likely resist its dispelling. It mostly depends on how the relationship between mage and spirit evolved during the binding and how it was established in the first place.
I dunno who wrote it in the first place, but TMRE says:
And RoP:M says:
I have always interpreted it as the effect of the fact that different ways of MR do not stack, but both Parma and Might-based MR are under the full control of the character, who (as long as he's conscious) can always choose to suppress them (not cast them in the first place for Parma). It is my long-standing interpretation of the RAW, which is going to stay, that sapient supernatural creatures are always able to suppress their Might-based MR just like a magus can do for Form. IMO the magic system would be silly and contradictory otherwise, so I treat that quotes as the effect of the fact that a mage with Parma and Might can always choose which form of MR to use and which to suppress.
Hmm, I think you were trying to convey something really weird, which I find myself in severe disagreement with. Ablating is causing permanent harm, with the risk of destruction, to the spirit, for your own gain. Commanding is at worst compelling the same spirit to perform a temporary service under duress, typically with no permanent harm to the spirit. In no way it is any wickeder that using ReFo Hermetic magic to do the same thing. Binding, well, it is true that it exposes the spirit to long-term imprisonment, but at least it makes no permament mutilation of its Might, and it is theoretically possible that some spirits can be persuaded to agree to the binding, especially if it is with a person, by the same means a spirit can be persuaded to become a familiar. If anything, there are spirit magic and Verditius Mysteries that expose the spirit to a much more painful and harmful binding, which essentially act like Ablating. And there is nothing really "unclean" with Binding or Commanding a magical or faerie spirit. For these reasons, I deem that full Infernal nature on Binding and Commanding magic and faerie spirits is really unwarranted and excessive. Taint like on Summoning may be acceptable, since the powers can be used on demons as well, or even the power switching in nature from simple Taint to full Infernal when one uses them on demons, but Binding or Commanding magic and faerie spirits is not doing anything more wicked or evil than doing the same or similar thing by other (non-)Hermetic means, so there's a double standard here. Such powers should have the same standard as Summoning.
See my reasoning above. IMO making Binding and Commanding Infernal-only is a bad choice in the first place.
But the Goetic Arts don't work on Divine spirits, so the point is moot.
You can do the same enslaving with vanilla ReFo, or create a worse enslavament (which also drains and destroys the being) with Bind Magical Creatures, Spell Binding, and Hermetic Empowerment. Since you can develop Binding by means that in no way, shape, or form involve dealing with the Infernal, there is a distasteful double standard at work here.
This is grasping at straws. I understand a basic development guideline was at work here, by which only the Divine and Infernal Realm can bestow general MR, and this influenced decisions about the nature of Binding. But this had nothing to do with Commanding anyway, and making it Infernal-only is bad overkill. Nonetheless, even Binding as Infernal-only is deeply unsatisfying, if a character is using it for the agelessness only, and not on demons.
IMO a much better settlement of Goetic Arts would have been: Ablating is always Infernal, Summoning, Binding, and Commanding may be Infernal, Magic, or Faerie but are always tainted (register as Infernal to Divine detection). Binding a magic or faerie spirit only gives (Form) Magic Resistance, you need to bind a demon to have general MR. Using Goetic Arts on demons causes the power to register as Infernal to magic and faerie detection.