Can't speak for you, but I don't think I've ever flown with an instructor and not learnt something. Even if the only thing I've learnt is how not to instruct. (In fact, come to think of it, I try to learn something from everyone I fly with, whether student, new PPL or experienced pilot.)
Also bear in mind (if you didn't know already) that there is a minimum hours requirement for becoming an IRI. Can't remember exactly (but it will be in LASORS) - I think it's something like either 200 hours IFR or 50 hours simulated IFR. Sure someone will correct me if I've got it wrong.
FFF
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