i think it could be programming. if all classes have a 15 action limit the programmers only have to write out 1 program and not 7 different ones. we are always rushing them "quick, quick give me the next patch i need it now," we are like some kind of junky that needs their next hit :P

it could be as mentioned streamlining there was a lot of crap abilitities that never got used

or it could be that the old system with the number quota was tanakas vision of how abilities should be limited, and this system is how yoshi thinks it would work

(or i could be way off and it could be something else :P)