Spell Resistance Rule [3.5] Mis-Written: A Modest Proposal

[Scipio_77]

I don't think there is necessarily a misspelling. "Volunteering to let the spell affect you" and "using a standard action" are not mutually exclusive, so there is no conflict between B and C.

Regardless, your suggestion would still be a perfectly fine and understandable houserule. A clever DM also makes it reward NPCs in encounters just as much as the players.