Right now, from what I understand, a lab text can only be used to duplicate the work described in it. If it's about a spell, it makes it easier to learn the spell. If it's about an enchanted item, it helps produce more identical items in the same time.
So basically, if you're powerful enough that lab text is useful for you, but if you're not powerful enough it's useless. And once you've used it, it has no more use for that specific magus, since he now has his own version of it, written over the season it was used.
Could there be more use for lab texts? For example, could they be used for study and reasearch as well?
Let's say that a magus is not yet powerful enough to learn a spell described in a lab text. Would it not make sense that, by studying that lab text and working in his lab, he can gain insights into magic, or possibly invent a similar less powerful spell more easily? It would seem intuitive to think so.
Picture a magus who, as one of his long-term goal, wants to be able to learn and cast Hermes Portal (ReTe 75). Out of apprenticeship that is out of his reach, but nevertheless is has secured a lab text describing the spell. Now and again, he comes back to that lab text, trying to understand the spell. Each time he studies it, it provides small new insights about that specific magic, based on his own improving Arts, but he still cannot use it. He create spells that are more limited in power based on it, but each time they only cover one part of it. After decades of work, he finally is able to learn the spell, but now has a host of similar magics learned throughout those years. (This sounds much more realistic that what we usually do as players: calculate the Lab Total and decide if the magus can learn the spell. Yes? Do it. No? Well, do something else this season, as that lab text is useless now.)
How would you describe something like this under the current rules? Would it be under Pratice for Arts? What about spell invention? A very small bonus to his lab total, replacing the similar spell bonus (let's say half the usual bonus)?
Just random thoughts...