There are published force - time graphs; most unfortunately from the sellers of the pads
This is from the Remington Super Cell
https://www.thefirearmblog.com/blog/2008/01/04/remington-supercell/

The curves do suggest that good pads dampen some of the recoil, and spread the duration of the recoil impulse

Sharp kids smile
https://www.flintsciencefair.org/wp-content/uploads/2020/05/95_Display.pdf