I'm a big fan and former owner of Kencraft. Had a 23 WA with the same problem, If you call Kencraft they will send you cables for free if you have had this problem persist. They had a routing problem with there 1999/2000 boats.... OK I just reread the post, 1996 Kencraft will need new cables and a little to old for the factory to cover it.
Is the throttle sticking in the early part of shifting the engine into gear and giving it gas or the whole throttle distance. If its in the early stages it could be the shift linkage in the motor and not the cables. I had this problem with a Johnson 150 and when the cables were disconected from the engin everything worked great. What I found is the shifting rod has two O rings where it enters the lower unit by the water pump. The housing of theses "o" rings becomes corroded and binds up the o rings around the shifting rod.