Why do Hermetic Magi use Redcaps to send messages?
It's beneath magi to use magic for such petty tasks, particularly if it wastes vis
They worry about Arcane Connections and use mundane scribes and mundane messengers
It's an old tradition and traditions die hard
Redcaps are protected by the Code of Hermes and thus secure (well apart from giants, bandits and other hazards of the roads)
Sending messages this way reinforces an ancient Mercere ritual that keeps the Order whole
Everyone likes receiving letters rather than emails... err I mean telepathic messages. Nothing says Wizards's War like a Redcap delivered scroll of torrential abuse!
It keeps the Redcaps on the streets and out of the laboratory or disturbing those pesky grogs
Redcaps are more than just messengers, they are spies, provocateurs and informants
It's a Mystery Initiation script requirement / a mystical Pilgrimage
Other (please detail or discuss the meta-game aspect)
Timothy and I were discussing this over lunch and we got to thinking... with such magic at their disposal, why would Hermetic magi even bother to use Redcaps to send messages, letters or other items apart form the meta-game reason that this makes for more interesting stories as such items can be intercepted, stolen, lost or destroyed along their journey.
Sort of leads on to a bigger question of why are there Redcaps at all, or perhaps to be fair, why do Redcaps walk the roads (or Faerie trods in the case of Hibernia - glad to see someone spotted that concept although I was hoping to steal that for my blog) instead of just using magic to teleport everywhere. Perhaps they do in some sagas., but an integral concept (and one that Gifted Mercere magi ascribe to every few years) is that Redcaps travel mainly by mundane means - magically assisted to be sure, but there's something about the actual traveling the roads that seems important here.
Because hermetic magi do jot have the abipity to do so. Alo hermetics have the potential to learn to teleport themselves and or items, but most cannot because they havw walked other paths. Potential and capacity are 2 different things. Still, most of them still need a fast reliable and trusted system of communication. Th redcaps are that communication system. They are the DHL or UPS of the age.
The power creep of the last 2 editions also creates th problems you mention, but they are far from absolute
Mecere in their capability of messengers, fulfill another important task at the same time, they know where magi move. say that you want to send a book about how to prepare good dishes through the use of herbam that you have promised a criamon by the name Gluttous Maximus, you did this promise last Grand Tribunal and it has now gone about 20 years since your last contact with him. You do not know where he is any longer as both you and him are terribad penpals. So you ask Swifty, the Redcap, as a redcap he is constantly updated on where to find various magi in the order.
It might be that he still reside at the Covenant "sus et proicies tomatoe" but you also remember that he had his enigma that had something to do with a place somewhere not far from Lavant, or was it Thebes tribunal. You know it had to do something with foreign spices. So how are you going to find him?
Creating and maintaining a set of arcane connections and making the spells and devices to use them is a pretty serious undertaking. Protecting and monitoring an area outside of the aegis to employ them is also a task that takes time and energy of at least some grogs.
The already existing network of magically augmented highly trained agents with their own network of teleportation gates is probably a more reasonable choice for most communication while some magi may sometimes set up arcane connection based communication arraignments between one another (such as the horn of champions, the items used by the outer circle of magvilus, or even a simple pair of eye of the sage spells).
Redcaps also bring all sorts of news of the world and the order not just what someone chooses to send you. Redcaps act as brokers finding you the text that you wanted or the specific type of visa that you cant get yourself. They can tell you who wants and enchanted item that you can make make with your arts and suggest what sort of a price that person would be willing to play.
Independently of the ArM version (from ArM2 on), I always held the opinion that magi had sufficient means for fast message exchanges within groups trusting each other enough to exchange Arcane Connections to places, items or persons. These networks and their communication protocols always benefitted from being kept a close secret: information about them leaking out would lead to rumor mongering in the Tribunal and perhaps Quaesitorial investigation, Hermetic or social attempts to break into the communication, and general suspicion and paranoia. No need to inform young magi at all - even if their players just bought a couple of Tribunal books.
The prohibition of scrying in the Code of Hermes further encourages secrecy about them. Clever cabals like the Fraternity of Samos [see TMRE p.128 Electus] likely use their Initiation Scripts to obtain Arcane Connections to mid-level members, to include them into their fast communication network without even needing to inform them of its existence before.
So keeping the generally accepted, well understood and well protected (by Code and Peripheral Code) Redcaps for all official and above board communication, including bulk mails like books and lab texts, polite letters, formal invitations, Tribunal paperasse and those letters necessary even between bitter enemies (at least the declaration of Wizard's War needs timely and reliable delivery) really holds the Order together and contributes to a feeling of unity and mutual dependence, without which the Order might quickly disintegrate into cabals.
There supposedly are about 1,200 hermetic magi. Most of them specialize in specific arts or technique/form combinations. Given the number of possible combinations, it's unlikely that more than 10% can handle the high level spells necessary for easy and fast communication (Cr(In)Im 35) or plain teleportation (ReCo 35, disregarding casting requisites). I currently play in two long-running games, and in neither of them is there any player magus (out of a total 14) who has learned such spells.
The Redcaps serve as a fundamental communication and trading network that is available to everyone regardless of the focus of their magic. They also serve as register, because being able to teleport somewhere or even travel quickly doesn't necessarily mean you know how to get there in the first place. The Redcaps also serve as neutral intermediary in delicate situations, when personal contact might escalate into open conflict.
In all honesty this is their most important role. Sure these could all be done by Gifted and probably even be done "better" by Gifted. But by the magic of comparative advantage Redcaps are the ones who should be doing it. One Gifted might be worth five Redcaps, but five Redcaps aren't worth one lab rat. So the Redcaps do mundane tasks, and the lab rats, eat cheese in their lab.