Interesting that you mention loading a brush. Yesterday I posted on B&B about not being able to get good lather out of a L'Occitane Cade soap puck, compared to a Tabac or Truefitt &Hill soap puck. The response from one chap was to only wet half the brush. I followed his advice, and added to it by changing from badger to boar, and I got excellent lather out of the previously annoying puck.
You are right, what makes shaving fun is the variables. This in turn means having to keep some variables constant in order to check the effect of others. One variable I like to keep constant is shaving cream when I test a new razor or razor/blade combination, and for convenience I settled on Trumpers shaving cream as the constant in such evaluations. Much to my astonishment, my new and most expensive razor, a Weber DLC, performed in a very sub-average fashion with Trumpers, but worked much better with Cade soap. I didn't think such a thing was possible, but that razor with a Gillette Super Thin blade (another constant) wouldn't shave hair off my face properly. Instead it needed a very sharp Feather blade and no Trumpers to deliver a mild shave.