You know, I have never understood why, in a game where everything has max hp per hit die, the same hp caps for spells are maintained as in P&P, in which most monsters have only average hp per hit die.
For that matter, I have never understood why, in a game like 3e which upgraded hp for damned near everything, the same hp caps for spells are maintained as in previous editions. Do you people realize that we are actually using hp caps for most of these spells that are holdovers all the way from 1st edition?! That's patently ridiculous IMHO.