And then later from PE....
If you have good apparent hardness with no hardener present, that is a clue. Something is helping give your emulsion a cohesiveness it does not deserve. Of course, this might just be cold gelatin on a repelling substrate. To test this theory, dip a small piece of the stripped emulsion into warm water (75 - 95 deg F) and see if it dissolves. If it does, then it was cold gelatin coming off a repelling substrate. If it remains cohesive, then it appears that something hardened your gelatin while repelling it from the subbing layer.