Yep, just found it, so I would have to say to not mix them.
"Because the direct drum is a dynamic apply, the waffle grooves cut in the clutches allow it to relieve the fluid between the plates. That's why the direct clutches are waffled and the rear clutches are not. The rear clutch is on in all forward gears so it never really gets a dynamic apply"
It was quite some time ago that I was doing transmissions professionally, so part of my problem is just plain memory.
The fact that I did all the major brands and types makes it hard to separate one from the other in memory.