My system would be, press and hold the DSC mayday button. Sail/motor back to the casualty shortening foresail but leave enough to effect an HEAVE TOO on the windward side of them. Put the end of the Main Sheet through the reefing penant nearest the boom end and pull though as much slack as possible. Tying this end to your own life-jacket, get into the water and proceed to the unconcious casualty, untie the sheet end from you and tie to them with a bowline. Use sheet to get yourself back on board. Ease the jib to the opposite tack and let the boom swing leeward by releasing the sheet, grasp the sheet between winch and where it goes towards the reef pendant, 3 turns round winch and wind casualty up towards the boom end. Now stop the winch with the jaws. Manoeuvre casualty back on board by turning into wind and get them over the rail. Untie sheet from them, unjam winch, go back to Heave too and attend to casualty first then update your radio message.