Look at the stages they've successfully defended the jersey on. Rather like the stages they successfully defended Cadel's yellow jersey on in 2008, they weren't major mountain stages. Once we got to the major mountain stages, that was when they suffered. They successfully kept Evans in yellow for five days in 2008, just like they've kept Gilbert in red for five days this year.
Honestly, I know they were not as much help as Evans would have wanted in the mountains (more out of bad luck and the team not really knowing how to approach a season based around GC riding than anything else - Kohl and Dekker were meant to be big mountain helpers but turned out to be frauds), but you make it sound like they were hopelessly incompetent and the second Evans got the jersey he'd be having to pull back every single breakaway on his lonesome, even on flat or transition stages, and they'd be being shelled by sprinters' teams.
They aren't children amongst men.