When I sailed F18 I'd (skipper) always stay on wire until the first gybe. It was worth a few boat lengths to be out there driving the boat hard while the crew was pulling the kite up. A couple of times we also swapped jobs at the bottom mark. I'd hand the tiller up to my crew and then pull the kite down. This was also fast but only in conditions where you didn't need to play the main at all as trying to hand the mainsheet to him was slow. With regards to weight I used to drive from the transom when on trap so weight distribution was almost identical as we were similar weights.