If a pc has the twist away ability but he can't recognize the spell that is casted on him how can he use his twist away ability.
In the case of finger of death I can understand it even without a spellcraft check. Because there's a green ray going to the pc.
But otherwise it smells like metaplaying.
A PC can use the twist away feat even if he doesn't recognize the spell, because the twist away feat has no requirement to identify the spell.
If it helps you to picture it though, remember that the PC also gets a saving throw even if they don't recognize the spell. It is being required to save that triggers the availability to use the feat.
Heck, the PC gets a saving throw even if they're unconscious. So it's not that weird, relatively speaking.