That's true, and like I said I see your point. I would also tend to agree with your point, but there has been a tendency for vague things like this to be written which later get clarified. Muto Vim errata, wards penetrating to name a couple of examples.If you write the rule one way, then the example should be illustrative of the rule. The example doesn't make any mention of House affiliation. I prefer to say that the Bonisagus magus retains the ability to coordinate multiple assistants in the lab. Some apprentices might have this ability (see below, but say after 10 or 20 seasons of working with the Bonisagus, depending on when they realize the Puissant Magic Theory virtue).
I'm not trying to be argumentative, but what happens to a Bonisagus magus who has an apprentice and takes on another apprentice? Does his ability to be helpful in the lab happen immediately upon the Arts opening? Doesn't that seem a little off somehow? Especially in light of how the House virtues (and this is another House virtue, albeit more limited than Puissant Magic Theory) shouldn't it take 10 seasons to be realized?
As for the thematic of the covenant, well research does not mean group research. We each will have very different areas of interest, so I don't think we'll work together that often. It makes sense for longevity rituals, perhaps for making enchanted items, possibly for familiars. But not as much for spell invention or original research, IMHO.
Anyway, saying that Bonisagi have the equivalent of Puissant Leadership when managing a lab team is ok. It raises the cap for the number of assistants.
Very true...but say we want to invent a spell to realize a research goal, and we want to do it in a season, and another assistant will put us into that position... Will we, as a group lend ourselves to our sodales to foster research in this fashion? I dunno, maybe we won't. It's true that our research is different, but we all have enough knowledge of Magic Theory to be of use to each other in certain (limited) instances.