But what if the ball strikes the pads really hard & the bubble wrap pops?
Impossible for the bubble wrap to pop behind the facade. Even harder if you had a thin layer of foam in front of it.
Think of how hard you have to press to pop bubble wrap between your fore finger and thumb? A ball which has a bigger surface area striking the pad would have no hope of bursting a cell, let alone enough cells to make any difference to the pad.
Also, small pockets of bubble wrap would not bounce/rebound as much as foam etc.
There is alot of merit in this idea and with a little investment in design, I reckon the lightest pads ever could be made that would also have test level protection.