Klay dropped 28 points on Allen on 10-17 shooting in less than 30 minutes during the regular season. It's far easier for Klay to lose Allen than it is for Durant - he's better at running around screens, the Warriors' sets are far more intricate in getting shooters open and he can put it on the floor against Allen better than Durant can because he has a lower center of gravity and shorter arms.
I counted about five occasions where Klay put the ball on the floor and got past Allen.
His video shot chart -
http://on.nba.com/1EWMW3R
Missed five open shots, a few of these were him dribbling right past Allen (he missed two shots in the paint contested by Randolph, one missed after Lee contested his shot on a 3 and one shot where Allen hit his arm on 3, which was deemed a block). The ball just didn't seem to go his way often enough - Curry definitely needs to give him the ball more instead of playing a one-two game with Green.