Someone should do a survey that asks if anyone has actually been successful in using this DMV to actually find and fix performance issues or if they use other methods to initially detect a performance issue and what to look for.
I cannot speak for others but I've never used this DMV to troubleshoot performance and don't actually know anyone that has, successfully.
RBAR is pronounced "ree-bar" and is a "Modenism" for Row-By-Agonizing-Row. First step towards the paradigm shift of writing Set Based code: ________Stop thinking about what you want to do to a ROW... think, instead, of what you want to do to a COLUMN.
Change is inevitable... Change for the better is not.