Agreed. Idiotic old school philosophy. The excuse Grobe usually rolls out is "well how will we know that he's tough enough to count on?"
You don't. You don't really know that ANY player won't get injured on a given play. You just play them, and when they get seriously injured you take them out.
Apparently there was a WF event in Durham recently, and the writeup was posted on Scout. I won't post it here, but a salient point was Grobe's statements at the event about Josh Harris. Apparently, Grobe thinks the kid is full of potential, but feels like he can't count on him b/c of "toughness" issues. After the Va Tech game, he said we gameplanned around Josh Harris for the MD game. After one of the opening drives, Grobe says "he got popped and just limped off the field." Obviously Grobe wanted him to sack up and stay on the field.