What we see in this viddy is the end result of many years with 200-300 days per year spent training as a team. Looks effortless for a reason.
To get started practising this trap method, I recommend performing it on the dolly ashore. After a good 30-60 min of doing nothing but coming off the wire, scrambling to opposite side, then getting back out, you will develop a rythm and it will start to become ingrained in your nervous system.
My one day with a coach had my learning to come off the wire on my knees to be quicker through the tack. I got reasonable at it but have since lost my touch/nerve after not performing it regularly (when not racing) and not sailing for a few months at a time. Tried it last w/e at Catfight and totally botched it in a race...went sliding across tramp and crew ate the boom. Gotta practise ashore before using in race.