The general consensus seems to be that Vulgar Alchemy is one of the most, if not the most, "broken" Virtues of TMRE. Most complaints seem to fall into the following:
a. It's a ridiculous amount of work for very little benefit.
b. The possibility of getting a bonus depends far more on the ability of the experimenter than on the appropriateness of the bonus.
c. Having a fixed set of S&M bonuses limits player creativity, and makes every new S&M bonus published effectively a retcon of current canon.
d. The current system forbids having an item with more than +13 total bonuses. A number of materials already violate this. For example Gold and Silver have a total bonus respectively of +8 and +10 from the corebook, and of +10 and +8 from the section on Vulgar alchemy which presents new shape and material bonuses gained through the use of Vulgar Alchemy. Thus the Vulgar Alchemy rules are not even self-consistent.
Can we "fix" Vulgar Alchemy? With "fixing" I mean, in order of importance:
Make it a Minor Virtue that is neither overpowered nor underpowered.
Make it interestingly related to "Alchemy".
Change as little as possible from the current system.
Aha! I have a rough idea that would work very easily. Have Vulgar Alchemy allow you to use the Alchemy (or Magic Lore) Ability as a modifier on the Extraordinary Results chart in some fashion when doing original research (HoH:TL) specifically for new Shape & Material bonuses. Perhaps the modifier would be something like (Alchemy + Magic Lore)/(4 or 5), rounded up? It could modify one or both of the rolls, but I'd have to read back through original research to be sure how best to implement this.
I'd keep the name and rewrite it entirely as a virtue doing something with Alchemy.
I like it if players invent their own bonuses, if, for instance, you wish to use your house symbol in your talisman, this signifies something, might as well give a bonus.
Many shapes or materials with mythic qualities are not yet written down, they could be judged by the troupe better then by the rules.
The S&M bonus lists from the books are just examples, rather than complete lists. A magus can always incorporate other materials or shapes if they seem mystically appropriate for the type of enchantment, with the player negotiating the actual bonus with the troupe.
The S&M bonus for an item is normally limited by your Magic Theory score. With Vulgar Alchemy it's twice that; if you experiment, your experimentation bonus (simple die + risk modifier) is also added to your limit.
Simple, and it encourages the player to come up with mystic resonances for materials and shapes (to take advantage of the higher limit) and possibly to experiment.
Assume that the S&M bonus list is exhaustive, unless a magus adds to it.
A magus with Vulgar Alchemy who experiments with the creation of a magical item can incorporate a new shape or material in the item providing a yet-unlisted bonus. The bonus is negotiated with the troupe. Thereafter, the magus can always use that S&M bonus, even when not experimenting. Any magus who gains xp in Magic Theory from someone who knows an unlisted S&M material bonus -- including exposure xp when acting as a lab assistant -- gains knowledge of the bonus if the knowledgeable party so chooses.
There is a good point here. Is the list exhaustive or not. Based on Atlas's behavior I would have said the intent is that the list is not exhaustive. Otherwise they probably wouldn't print a few more here and there as we go. I would expect an exhaustive list to be built differently. And we know Atlas has more to work with than what they've printed since they haven't printed tons of stuff from the WGRE. But then there is Vulgar Alchemy that makes it seem as though the list is supposed to be exhaustive. Definitely YSMV. But fixing Vulgar Alchemy definitely depends on that viewpoint. If the list is exhaustive, then more can be added via Vulgar Alchemy. But if you get the bonus from anything, even without knowledge of it, then Vulgar Alchemy needs a totally different working.
Also, I like Ezzelino's transmission idea. It's pretty straight-forward and essentially works the same well as Spell Mastery special ability transmission.
The OP remains relevant. As an additional thing to consider with Vulgar Alchemy, and validate Marko's statement of the math being out of line, consider the case of silver. There was a magus with Magic Theory 10+ and (Perception + Magic Lore) 18+ at the absolute minimum, who decided to make at least 33 separate magic items with silver. This magus published their findings on how silver harms wolves in a Q20+ tractatus on Magic Theory. The skill and effort for this feat should make Bonisagus himself look like he needs to take off his shoes to count higher than 10.
Hermetic Breakthroughs should not be easier than formalizing "silver hurts werewolves."
The simplest solution(s) I can think of...* Any who reads the lab text with the integrated component learns it
Magic Theory tractati may teach up to its base Quality (6+Com+bonuses) in components
Testing the Component is EF 3+proposed bonus+scope modifier (3 for minor focus, 15 for Hermetic Technique, etc)+/-story bonus
You only need to experiment/test the component once, and cannot try for the same bonus again if you have failed previously
To be fair, the guy who SG'd for the person who formalized "silver hurts werewolves" probably got the best possible story bonuses due to that being so appropriate. But your point stands, it's still way too difficult and time-consuming to be realistic.
I can't speak of the playtest process. Well, I can, but the only evidence I have of its existence are the credits at the beginning of various books.
Some things escape playtest too crippled to be used. Shot while trying to escape, I suppose. VA is one of these. Then there are things that escape playtest so awesome and powerful, that the pharaohs must write them out of history so that no one will remember their existence. Then there are things that work just fine.
(The game's research, otoh, almost always seems well-reviewed to me, the place where a lot of hard work seems to go. (Of course, I do not consider myself expert about nearly all of these topics, so I might easily be fooled since the Judaism section of RoP:D isn't as good as it could be im(in this case, not very humble)o; Chelm does not belong, nor do Baale Shem, nor the idea that Rabbinical Judaism will have more problems with Hermetic Magic than Christianity (ha!) and especially than Karaitic Judaism (quintuple ha!) and....) On the whole, I find myself learning quite a bit from AM supplements.)
Oh, you did? Oh... Oh my. That is truly horrifying.
I've noticed there are a few too many "times 3"s in the equations that make everything longer and more difficult. If we remove those and make the Quality requirement for the tractatus equal to the bonus, would that not fix most of it?