When trapezing down wind, you can not gybe from the wire. I'm pretty sure it is impossible if you want to gybe quickly. When you tack, the boat turns up into you. When you gybe, it goes bye bye, and you're left hanging in space.

I learned this little tid-bit on Saturday. Port/starboard situation, I had no rights, and waited too long to determine that collision was imminent with out action. I pulled the tiller, and was unable to get on the tramp before it went over. Bad start, and I was at the back of the fleet at the windward mark, when I tipped I had made it to about the middle of the fleet though.