I had a pair of skis stone ground once and they were unskiable by both my friend and I on beginner terrain. We have the same boot length and switched, they skied so poorly we both felt unsafe getting down the hill. The best we ever figured out is that they screwed up the structure so badly that the skis resisted edge to edge changes, or just grabbed when flat.
Jer I understand what you're saying because all too often we blame our equipment instead of our skills, but from what the OP said it could very well have been something really screwed up with the skis. This was most likely on hard packed icy terrain where problems are magnified (as compared to soft snow.)