That thread has a ton of information on all things WoC. Cho's HM was drastically reduced in difficulty since the thread, so you should be able to get some ideas that work.
Quick Answer: Tactics.
Quick Builds: On my para, I used a mesmer, MM and healing necro. On my warrior I used two channeling rits (level 16 SW/Arage) and a monk with half a skill bar of domi magic.