Recently I've been singlehanding my Catalina 310 alot and I've noticed that in similar wind conditions on a beat or a close reach I can attain the same (or nearly the same) boat speed with just the 150 Genny as I can get using both the genny and the main. Also, the boat seems to point just as well with just the genny and of course there is a lot less heel. I just don't seem to gain anything upwind by using the mainsail. Both sails were new last year. Any thoughts on whats happening?