I tried the method of laying the print on a piece of glass and taping the edges down. I used two prints I didn't care for, taking them out of the water I didn't squeegee them but just taped them to the glass and let them dry 5 hours or so. They looked great, flat, just like they were dry mounted; that is until I cut them loose, I couldn't get them off the glass. Both prints were ruined. I'm trying one now that I squeegeed before taping to the glass.
If I can't get this method to work I think I'll adopt it when it comes time to mount the print but instead of tape I'll just use photo corners.