One problem with "measuring" felt recoil is that you'd have to use not only the same loads, but the same gun. So issues like gun fit would enter into the picture. Of course if you're comparing different loads using the same gun, even though the gun in question might not fit some shooters as well as others, you should be able to get an answer as to whether Load A kicks harder than Load B. And that would seem to be a valid test--as long as the ejecta weight and velocity of the two loads is the same.
