IMO if you get grabbed/killed at the edge of the stage you simply got outplayed. A simple solution is to just stay away from the sides if your damage is too high to mash out of the grab...DK can pick anyone up and throw them into the blast zone for an easy 0% kill.
Besides, that means it could be a good counterpick for DK against a bad matchup, say for instance MK.
I feel like this discussion doesn't belong here.