I have nothing proven to add. I did however put atf in a ps system after an engine swap. After the atf the pump leaked a lot. Would I do it again? not a chance. Scientific? not at all.Wrong conclusion? possible.

Anybody know what the seals are made of? It could be looked up in an o-ring handbook to see if they are good for both fluids. I do know I would never put ps fluid in a trans. Beyond that who knows.