I think we go to Perk often enough. It simply can't happen every game. You've got to go to Pierce... you've got go more to KG, you've got to go more to Rondo, you've got to go more to Ray, etc. etc. Then you consider that Ray, Pierce, and KG alone need a huge bulk of the touches.
Overall it's quite hard and at times impossible to just go to all of them at the adequate amount and have the offense running a smoothly as possible. You go to Perk, maybe you start messing with Ray's touches, etc. So I don't think it's as simple as "we have to go to Perk more often".