As far as a race committee waiving the rule, that depends upon the interpretation of the rule, which we still do not have. If it includes tethering, and if tethers are attached to trapeze harnesses, I would assume the rule would have to be waived for long-distance catamaran races.
Actually I think most of us only attach a tether (a.k.a. chicken line) to the dogbone - not to the harness itself. David and I did this because we didn't want another attachment from us to the boat. It worked just fine that way.