Gene, I found out that tight chokes make you a better shooter by accident. I went from shooting a screw choked O/U, at registered sporting, to a fixed M and M choked O/U. There are many, many presentations that do not need a M choke to break the birds in competitive sporting. When I started shooting the M and M fixed chokes I was an A class shooter, and had plateaued in my attempt to gain Master class rating. I quickly punched up through AA to M with the tighter chokes. I shoot regularly with my buds who all change chokes "according to the situation", basically trying to use the most open choke they can get by with. For me, this introduces negative thoughts. If I do that I'm really saying to myself "I probably can't hit this bird every time with a M choke, so I'm going to put in a S (Skeet) choke constriction to cover my bases". Negative thoughts, and those thoughts are super-important, in competing or in hunting.
If you do a search on Shotgunworld about this you'll find many others who have found the same thing to be true for them.
Best, SRH
BTW, what's the bore size on that M79, 'bout 0 gauge?
