A bit off-topic, but your shooting story sort of reminded me of one of my own (and how it likely relates to my pool game).
During my army basic training, at the rifle range they gave us a lot of practice latitude. I got it into my 17-yr.-old head one day to buckle down and see how good I was. So, with a whole box of 30.06 clips at hand, and my M1 garand on a sandbag rest (open sights), I started knocking down silhouette targets at 300 yards. After all the ammo was finally gone, I noticed the drill sergeant over my shoulder, watching me and shaking his head. I had never missed once! But, when the official ‘sharpshooter’ test was staged (varying/surprise distances/time limit/offhand stance), I barely qualified.
Much like my pool game then, I was an outstanding shot-maker, but couldn’t play position or recognize patterns under pressure.
I was a range bum with nothing else to do while recovering from an injury. Noticed a medium sized older guy, a bit of a pot gut, nothing looked too special about him. Main thing I noticed is that he never brought anything but a Garand, and he stood on his hind legs shooting it at 100 yards, as far as that range went to. When he started a group he didn't waste much time getting it downrange. The range owner's father was around one day and couldn't resist telling the man he would shoot better if he slowed down. We walked downrange to change out some other groups and looked at his target. You could cover his group with your hand! He was a marine, retired, and had a more than respectable rating with the Garand in his time.
Talking about pressure, I was out of work and living off of pool and stock car earnings. My car wasn't getting the care it needed other than the things to keep the engine in good shape. For example, I had three bent shock absorbers and the fourth was gone. I timed in at the front of the fast heat, actually outside pole. That meant ten faster cars behind me and twelve laps to hold them off! I pulled the pole position car down the front stretch and that was the last I saw of him. However, I had a car drop in every turn beside me and I could pull whoever it was a little down the straight. This went on until coming out of the final turn of the race.
A car ducked under me with two wheels in the mud to pass. Dumb move, he hadn't been able to pass me in a whole straightaway. I built pretty good engines. When he slid up the track he hit my left rear. Two choices, back off and catch the car to come in third or fourth or plan B. I whipped my steering wheel into the spin and nailed the throttle down. The finish line was fairly close at this track, halfway down the front stretch. The spinning stock car took up a lot of room on the track too. I crossed the finish line in first place, spinning since I left turn four.
Between having to drive twelve perfect laps to stay in first and the grand finale I was totally spent. I climbed out of the car and had to lean on it and rest a few minutes before walking off. It is amazing how much energy we can burn just dealing with pressure. My knees felt like rubber for a couple minutes!
I felt similar pressure a few times playing pool or snooker but it was rare. Going around in circles was the primary way I learned to deal with pressure.
Hu