I personally believe
that choice between a loose-footed and a shelf-footed main is one of esthetics, that is, what you happen to prefer in terms of looks. Sure, a loose-footed main is easier to bend on or off, but how often do you do that? Virtually every non-racing sailor that I sail with, some of which have loose-footed mains, others (like me)have shelf-footed mains, just about never adjust the outhaul. On the few occasions that they do, it's usually time to turn on the iron genny anyhow. The outhaul is a set it and forget it item to most day sailors and cruisers. I also think that I could make just about any of the sail trim arrangements with my shelf-footed main, if I chose to, that one could make with a loose-footed main. I've been sailing with shelf-footed mains all my life and happen to like them. I also agree that most all new mains are being made loose-footed. When I bought my new shelf-footed main for my boat a few years ago, the guy I dealt with at North Sails confirmed my feelings that there really are very small performance differences between the two varieties. But he also confirmed that a loose-footed main is less expensive to make labor-wise, sells for the same amount as a shelf-footed main, and so the profit margin is slightly larger...