There are a lot of bad books out there. You "average" presumes that everyone is trying to publish books. My view is that a magus would not even bother unless he had a positive communication score, and libraries prefer to collect the higher quality books from good authors. Basically, if you have a Com of -1, no one will want to bother with your hack writing. If you have a Com of +1 or better and the Good Teacher Virtue, then many-many people will want a copy of your book, and it will recieve much wider distribution. Good books never die, they get copied over and over again. Bad books get forgotten about and are used as matress stuffing.
So 6 is not average. A 6 or lower is a candidate for kindling. Text that are being used for trading and scribal exchange should be 7 or higher, with 9 or 10 as an average, and going up as high as 12 or more. Then from Covenants, there is also a potential +1 for Gloss, +1 or +2 for Resonant Materials, @+1 for Clarification, and so on.
I think that is the difference. While it's true that that books written by average magi have a quality of 6 the average book that has copies made of it was not written by an average magus.
The coveants books has a discussion of different qualities of tractatus. The discussion assumes that, throughout the history of the order, books of higher quality have always been preferentially selected in favor of books of lower quality . So that by 1220 books of a quality lower than 9 are only of value for trading to folks who really don't have any alternatives. (in my opinion this group consists primarily of specialists who've already read all of the relevant high quality books in their field of interest that are readily available and so are eager for anything, and young magi who have nothing worth trading themselves .)
It seems to me that this assumption is based on ideas that I personally disagree with. Aristotle is Quality 10. St Augustine is Quality 10, Plato is only Quality 9. IMO, to say that Order is producing better quality works than the greatest minds in the Western world is frankly absurd.
Don't have Covenants. Didn't want it before. Definately don't now. To each there own. Anyway, I think I understand where everyone is coming from now.
Your Arisotle is much different than my Aristotle then. I rate his books at Q12 at least (Com +3 or more and definately a Good Teacher). Actually, I think I rated him at Com +5/Q14, just to make him more mythic, but I don't recall off-hand. And, since his score in Philosophiae is exceptionally very high, the book would be of an even higher Quality. Mythic Aristotle, Com +3, Good Teacher, Philosophiae 16 (or higher!); he could have written a Philosophiae Summa of Level 5, Quality 18! (+6 for writing two levels under his maximum for an Ability).
Nope, not yet. Do they have Aristotle in there? I am guessing they got it wrong then. Com +3 and Good Teacher, Philosophiae 16 or higher. If it is anything less, then it is simply not the same Aristotle I once studied.
Or, if they simply described a book without including any author details, then a Q10 Aristotle book represents a text that has been soaked, scortched, and stepped on, having a -2 or -3 penalty because of age & damage.
The Art and Academe qualities are probably talking about the copies available in 1220. So these are likely copies of a copy of a copy of a copy...and have undergone several language changes (Ancient Greek -> Arabic -> Latin): all of which adds up to an assumed degradation of quality.
I believe there aren't really any books books by Aristotle, certainly at the time. The "Aristotelian" books are compilations and editing jobs done from lecture notes, so to speak. So even their initial quality would be poor, and after all the translations and tribulations they have gone through over the years...
Personally, I don't think the Ancients should be given very high scores, either. Respectable scores, such as 10, perhaps. No more. It is modern Hermetic magi, with their long lives and scholarly literate society, that push the envelope. The Ancients got the basics right (say, level 5), and may have even rarely progressed further (say, level 10) - but only the long-lived dedicated magi can really reach heights such as level 16.
In addition to other posts magi are able to raise their Comm attribute permanently.
Your saga might be at low power level but magi are able to defeat mundanes easily even on this level. E.g. a sleep spell which can affect 100 mundanes has level 30. Not so much.
My young magus hasn't an attack type focus but even he got the group version of this spell and will raise its size with his flexible formulaic magic.