What is your reasoning?
If anything, it should get *easier* to identify cases, since you can see more of the puzzle without being blocked.
It might get harder to *call* the cases, but that is a matter of practice, and you get instant feedback if your communication didn't work.
I know it might not be as fun as calling from the solver's perspective, but I'm fairly convinced this is the best way to get fair, practical results with a sight blocker.