wouldn't that cause more double triggers, as opposed to having a foam layer in between the piezo and drum head?
Yep. But there is one problem, it doesn't fit on the lip of a drum as is. You are going to have to take a grinder/saw and get rid of the extra length on the side of the clip that fits over the lip of the drum. I will give pictures when I decide to do it, But it seems a rather easy process.
I have 4 of these actually that came with my Audix DP7 kit that I don't use, I wonder how hard it would be to fasten something to the top of them to extend over the rim that I could mount some foam and the trigger to?