I came upon this new exercise on youtube earlier. You grab on a high bar with one arm and a low bar on the other arm and do an assisted OAC or OAP with the top arm and an assisted one arm dip with the other arm. It might be a useful exercise for someone trying to build up to a OAC/P or a OAD or for someone who wants to train the pulling and pushing muscles at the same time. It's most likely not useful for GST, but still interesting.