[Mr V]

If you are worried about failure of a single limit switch then just wire in two so you have a back up. Use the NO contact and wire them separately and in your code have it stop if either of them put out a signal. Relatively simple and legal under last season's rules. Having one in the power path would not be legal under last year's rules and I'd bet that it won't be legal under next year's rules. Additionally the problem is finding a limit switch rated for the amperage that the motor is rated for along with the fact that it would kill that motor for the rest of the match.