Bugs wrote:

People say the darndest things. The only thing dual pistons do is to
keep the whole caliper from moving. The forces on each pad are the
same. Its the same as pushing against the wall or pushing against
another person, the pressure is the same.

........ But the brake pad area is doubled. Twice the stopping force,
which is what we're talking about.
Bugs

Every single piston brake I've seen had pads on both sides of the rotor.
The pressure that is produced by the single piston is applied to both
pade. It's just like a vice, each jaw pushes the same amount, even
though only one moves.
If you have two pistons, they push against each other with the rotor
in between. The force remains the same as long as the area of the
piston is the same, but instead of pushing against the other half of the
caliper with the other fixed pad mounted on it, the pad is being pushed
by the piston.

John