Simplicity is definately on the side of end boom sheeting.
For racing preformance, I dont think that mid-boom sheeting offers any advantage for the Day Sailer. The North American Championshilp has been won with end boom sheeting on every boat for the last 11 years, to the best of my knowledge. (maybe the 2006 was mid boom). Light air and heavy air, 20 to over 30 last summer, end boom sheeting has worked fine. To handle strong winds, have a good rachet block on the main sheet swivel and keep the sheet OUT of the cleat and hand hold the sheet at all times. That way you only have to release your grip on the sheet to respond to a gust.
Mid boom sheeting can be effective, but also clutters the cockpit and causes a tripping issue and extreme shin bruising.

To be effective, the mid boom traveler needs to be at least as far aft as the end of the CB trunk. Any futher forward the mid boom attachment doesnt offer any improvment over the ability of the boom vang to control the leech.
Just my $.02 cents worth.
