At my (large, multinational, Germany-headquartered) employer, I frequently hear "on the one hand side... on the other hand side" by non-native speakers. This always sets my teeth on edge. However, I have heard it often enough coming from many different people that I'm getting unsure of my intuition. Then again, it could just be incorrect usage spreading from non-native speaker to non-native speaker.
Is "on the one hand side" accepted usage, or is my hunch correct that it isn't?