I've just noticed that the enhancements "Prayer of Incredible Smiting I, II, & III" are showing as obsolete. There is a set without the word "Incredible" in them.
It would appear that 6 action points are required to get a 3% critical chance!
Does anyone else have this issue? (I've just submitted a bug report).
I did feel that light spells weren't doing as much damage as before but I've not tested it.