Henry@home said:
A person with sufficiently quick reflexes could foil this spell - a save would not be out of the question.
Sure they could, if:
(a) They had ranks in Spellcraft and were able to figure out what was being cast at them
(b) They had readied an action to specifically stick out their hand when the caster finished his spell
You can't just take an action whenever you feel like it.
If a PC actually goes through such lengths to prevent being caught in a Wall of Force, I say let him!