Always used the left foot for something whether on a tractor, driving a stick, motorcycle, or simply to actuate the brake. Growing up in NC, where racing is sorta’ big, anyone that has ever hopped on a track picked up using the left actively. I still do it, but only when driving aggressively(not assholish).
Just because I can, I left foot brake whenever possible/plausible - I’m sure it’s inefficient to mix heel/toe and left foot braking when I’m hooning my truck around (especially since it’s so laughably slow), but I do. I went through a phase during college where I tried to drive my same stick truck using the clutch once per trip (and did surprisingly well), but I realized that the LFB this enabled was mostly possible because I was going places slower, not because it was in any way better or smarter.
When I’m stuck driving any of my mom’s mid-80’s shitboxes with slushy automatics it’s left-foot-brake all day, and I find myself trail braking in neighborhoods just so I can get something vaguely resembling throttle response rolling out of any apex by gaming those primitive trans controller boxes.
I’ve tried it and it never felt right. I suppose if one did it enough it would feel natural and be quick. But day to day I am faster using the right foot.
Now at the track when I had Mustangs and a Supra then I would heel-toe in the turns. In fact I had a vanity tag on the car to that effect. Funny side story - had more than a few people comment that my tag was disgusting. Lol! I realized they were thinking of camel toe and chastised them appropriately for having dirty minds. They typically felt pretty dumb.
Still miss this car more than any thing I’ve sold.
Sold my 911 (manual) in 1991 and have had (automatic) Jeeps ever since. I’ve not used my right foot for braking in close to 25 years…and am still alive.
I had surgery on my right foot last year and used my left foot out of necessity during my recovery. I still use my left foot quite a bit even though I don’t have to anymore.