Those things have long fuses. They are more like a satchel charge then a grenade. You should be able to easily dodge it.
Nope, the commando grenade goes off in a second unlike the infantry section gammon bomb and can be thrown from camo on top of that.
I wiped 4 ostruppen squads in one go with a commando nade ambush like this. Granted the guy was vlobbing them; he basically had 0 time to react.