[oxymoron]

WtS% would show you the difference between a tight player that goes to far with their hands and a tight player that can fold. Also, some players will autobet the flop but give up on the turn. For them you will see a high flop aggression and a higher frequency of folding to a bet/raise on the flop. Knowing these things can make a big difference of whether to fold/call/raise someone.

An example would be two players with a 20% VPIP and an aggression factor of 2 but player A has a WtS% of 20 and player B has a WtS% of 40%. Bluffing/re-raising player A is a good idea where bluffing at player B is not.