I used greater reincarnation to get a 32-pt build for my cleric and paladin. This is what I read about tomes:

With Lesser (and Greater) Reincarnation, your tomes will gradually re-apply themselves as you increase in level, at the minimum levels tomes can be applied at.
If you ate a +3 strength tome, for instance, and then lesser reincarnated, you would get a +1 inherent bonus strength at level 3, +2 at level 7, and +3 at level 11.