[MOTORHEAD]

Are both the pads wearing unevenly ? How about the pads on the other caliper?
With uneven pad wear either the piston is cocking or the caliper is moving out of alignment with the rotor. Have you watched it while someone operates the brakes?
You could even set up a back-up camera to watch the brake operation under on-the-road braking operation, or as I said, replace the caliper, it's been driving you crazy for what, a YEAR ????

ps; Is the caliper a floating type or solid mount?