Nothing whatsoever. I just got a kick out of the pie plates. I just envisioned some old deer hunter with his trusty 30-30 trying a tuner and claiming it doesn't do anything.
I wanted to make a big detailed write up of my tuner experiences but I can't seem to find the time. I have used a tuner/tuner brake since I started shooting 600/1000yd BR. I work up a load, with the tuner installed, make it shoot as good as I can by tweaking powder/seating depth. Now, I tune a little different than some do as I want to find the middle of what shoots good and that may not be the very best groups that the rifle is capable of but it's also not on the razors edge and about to fall out of bed with the slightest change. This is what has worked for me as I preload at home and travel without any ammo tuning option other than seating depth. Then I shoot 2 shot groups changing the tuner and paying attention to POI more than anything else really and choose my tuner setting that way. For me, I find it best to do all of the load work up/tuning at or as close to the intended shooting distance that you can. Not everyone has that luxury but I tune at 500 and 930yd as that's what I have to shoot safely. I haven't ever tweaked my tuners during a match, I would've liked to a couple times but I have never taken the time to learn which way I need to go, so I fall in that camp of never touching them after they are set. I feel like they do give a broader tune window when picking a setting from looking for similar POI.
I am also of the belief that all of this "tuning" can be accomplished by load development without the use of the tuner IF a person takes the time to do so and learn what changes do what. It just goes back to more than one way to skin a cat.
Lastly, personal tuner experience where it was negative... I was getting ready to shoot the covid nationals and my rifle was shooting great at 930yds, consistent low 3" groups with very little vertical. I was at the point where I was done and ready to tweak my tuner setting but that day the wind was up and mirage was bad. I have two firing lines, one for 930yd and another for 500yd. The 500 was protected from the wind and so I went over there and decided to shoot my tuner test at 330yd as I had just built that target frame and hadn't used it yet. The 930yd load didn't shoot very well at 330 but after a few turns of the tuner rings it came into its own and I'm feeling pretty good. Next day I go back to 930yd and the rifle is shooting 12" of vertical and it's all over the place. I thought about it a little and put the tuner back to where I had it when shooting that distance and it went right back to shooting 3" groups with no vertical. THIS is why for ME I want to develop and tune at the intended distance or at least as close as I can get. Now, in the end, that rifle and I put in the worst performance I have ever shot and I think I shot the barrel out testing before the match.
As to the large ES numbers shooting better at distance than the lower ES, It's not that we intentionally try to add ES to a load to get it to shoot better. It's that we shoot multiple groups/ladders at distance and pay attention to what the paper shows us and that means more often than not, we have to ignore the chronograph. PC is real.