Agreed. I've found the dealership mechanics to be lobotomized flow-chart followers. If X isn't working, replace part A, if that fails, replace part B, if that fails, replace part C.
Why not just run the necessary tests to determine which part is broken?
Source: exhaust valve spring was broken, and dealership somehow wanted to sell me spark plugs and ignition coils, despite my own notes stating that I've swapped them around but the problem didn't move around.