Have you tried SimulationCraft? Idk if we have many monk DPS experts around that could help you improve really. I actually had to ask in my guild "hey windwalkers are the dps ones, right?"
I played a monk for all of 1 hour in the beta... and I was pretty drunk at the time.
As far as knowing when to switch, well. It's a game, are you happy? If you think there is a significant skill gap between you and the other raiders, is it worth the slower progression to be around people you may consider your friends, or would you rather find another guild. I've found that happiness in raiding comes in finding a guild whose atmosphere fits your attitude/playstyle.
"If the world is something you accept rather than interpret, then you're susceptible to the influence of charismatic idiots." -Neil deGrasee Tyson
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