Nick.

Brake switches, and brake bias switching are not thump brakes. Thumb brakes were built for some mc racers that could no longer use rear wheel foot brakes after major injuries. Bias switching has been used for years in F1 and nearly reflect how much front vs. rear braking emphasis one wants in their cars. Itz a little toggle button on the million dollar steering wheels that current F1 cars need to get around the tracks.

Hamilton shoulda known, IMO.