Problem with Monks is that they DPS way too fast. This is why Skill Speed is retarded even if the bonus you'd get was worthwhile, because you'd be using your skills in a rate that is unmanageable for your TP regen. And since Invigorate was made mainly with DRGs in mind, it has an extremely long cooldown because DRGs barely have TP issues to begin with (we are TP friendly because we have slower and more damaging attacks).

Monks are going to need something like 'Fists of Water' that gives them TP for each auto attack or something.