I've recently replaced all my incandescents with LEDs and found that the dimmer switches were of a type that... disagreed with the dimmable LEDs. While I was replacing the switches I noticed that 2/3 dimmers had unconnected ground wires. These were notably the ganged boxes, with the single-switch box having the ground properly connected, the other switch boxes grounds were simply bundled together off to the side.
That said, the switch ground is simply connected to the metal mounting bracket, and the bracket is connected to the switch box via the mounting screw, and the box itself is grounded.
I know that it is not ideal, but is it acceptable to leave the situation as-is rather than digging all the old wiring out of the back of the switch boxes? I've already destroyed my hands getting to this point, and also the ground wires are inexplicably painted over.
Yes, they are inexplicably both crammed into the back of the box and painted over, and I know neither how nor why.