Have you played Psylocke extensively? She already requires one full skill bar and half of another in a raid setting. Her damage priority cycle is already full. I can't imagine attempting to cycle on/off a visual effect every other rotation to activate the Power Cosmic. That would be a huge pain and a damage loss no matter which way you look at it.
The issue is Gaz said they were doing one thing, then did the exact opposite at the eleventh hour. It's not cool.
Psylocke's optimal damage build is as a hybrid. Hybrid items are too good in this game. If someone is running around playing her with the psi blades, they have intentionally gimped their overall damage in order to enjoy a cool visual effect. If your goal is to have fun with the character, play her as a mental build and enjoy her. Once dual spec comes out, I certainly will have that as an option. But if your goal is to maximize the character's damage potential, you can't enjoy the new toggle.