Well, I took the dive and gave this a try. I had a controller whose start/pause/reset circuit was clearly broken on the flex circuit. Purchased a new flex circuit on ebay. Carefully pulled the old circuit out and put the new one in. And viola, it works perfectly now. The controller is probably very close to what it was brand new. A worthy little project.
Tips: It probably goes without saying to start with a controller that has a rubber boot in good shape, and whose directional controls are functioning normally.