He has a point or two though. Firstly the arp explanation given in the guide is wrong.
About the professions: JC n Engi is bis. Not entirely sure though what's best. For shorter fights probably Engineering. The longer the fight goes the better BS becomes.
Also movement speed isn't necessarely a dps loss. It can even be a great dps gain if you play smartly and weave in an auto hit on the boss inbetween your gcds and your auto shot cd as auto shot and auto hit don't share a common cd in wotlk. Even better when you can place an explosive trap on the boss which brings me to my next point.
Two bis glyphs are without question serpent sting + steady shot. Yet as a third I nowadays play with the Explosive Trap glyph and the following specc:
https://wotlk.evowow.com/?talent#cxb...GIsxuAox0c:Lfi I have a draenei in my group though. I found the Explosive Trap glyph to be doing a hefty amount of dps. In that regards I think Engi is best profession overall even as you can sprint into the boss quicker to lay your explosive trap.