[bsftcs]

It is true that gaining new spells by way of invoking books does not yield a mana boost. However I do not think that will pose too much of a problem. when you have only one spellcaster you might of course consider bringing along a couple of mana potions, but you really should not get into much trouble with a lower mana level. I usually have my spellcasters learn new spells as fast as possible by invoking books, and that never caused me any problems with a low mana level. Perhaps one has to wait a little for the spellcaster to regain his or her mana before casting certain spells once or twice during the game, but I never found that irritating.