Lets face it, heavier women belong on the bottom... of a human pyramid that is! In a 2016 observational study conducted by yours truly, heavier women have a better center of balance than females of the lighter frame. Maybe you wonder how I came to that conclusion; as I was watching women shopping at the local box store I observed those who were getting bumped into by either other humans and their carts or those whom blatantly walked into displays. The heavier ones barely budged and just turned their heads to look at whatever obstacle has just made contact with them, the lighted females bounced back a bit (or, as in one particular case) simply fell down in the isle.
I digress, heavier women should be on the bottom due to their ability to hold steady during object force, as demonstrated in the example above. Medium build women in the middle and skinny bitches on top. This helps to form a secure human pyramid that you can damn near support a ceiling with.
Now, what happens when you put said female pyramid on top of a trampoline? Again, it's all about the women on women math problem; though instead of solid ground now you have unstable surfaces to work with. If the heavy chic is on top, she may topple the whore thing down.