Well Todd, you are just a good shooter! It must be all the good competition you shoot against on Tuesday night league that keeps your skills honed.Been using 7/8 on singles for a couple of years and my average has continued to go up, currently in AA . The biggest hurdle was in my own head so just find a load that you feel confident in and stick with it. When I miss it has nothing to do with the shell, it is the person running the show that missed.
I still use 1 ounce on handicap, 25 yard, but occasionally will use 7/8 and haven't seen a noticeable difference.