Brake caliper still sticking, even after brake piston seal and dust boot repair?

you know that the slide pins need a little grease on them and also i have heard the master giving some people prblems on this issue of over heating pads and rotors, i think this is a design error or problem with the proportion valve that has a weak return spring after certain long use( normal wear and tear)i have work for 8 days on my neighbors stratus triing to figure it out and i did now its fine with no problem at all, the poor guy took it to about 5 different shops and he payed dearly at ever one until he finally came and asked me to look at it.the best thing that i can tell you is to go to the junk yard yank a porportion valve and give it a try, it could be the master also so good luck