Coherent depends on who you ask
Once the TBI was diagnosed, the doc said that the body hardening that occurred over 37 years of martial arts, kept it from being a LOT more severe. But it did still have effects. The worst being, a decreased ability to contain violent impulses. That took some meds.
To your question about how it affects working out, you just called out one of the biggest risks I face in the weight room. So much so, I limit what I do. I've become a devotee of kettlebells, Bulgarian Bags, calisthenics, and gymnast rings; all things that I can avoid hurting myself. But I LOVE squats and deads. The problem is that, you are correct, I do not feel the pain caused by LA buildup; and I can plunge right into an injury without having a clue it's coming. I feel "pressure" where pain should; but I had to be taught to sense that. The sensation being akin to the pressure you feel in your gut before you rip a shredder of a fart. That's a similar pressure I "feel" in an area where there should be pain.
I'd go crazy if I could not do deads and squats. In fact, the reason I'm addicted to MMA, and those exercises at my age is because I "feel" those things the most. Not the pain, but the "shock" of contact in MMA, and the weight and pressure of a bar on my back, or in my hands.
And dude... yeah... the looks on those f'ing kids faces when I stood up still cracks me up; because they were talking shit the entire time they were stomping on me. It all went pear shaped for them when the biggest one (the one that was 18) who was currently putting in work stomping on my skull, got his balls grabbed, and pulled like I was doing a one arm lat pull down; he fucking howled. The surprise on their faces from that alone was gratifying. Then I stood up, left fucking ear hanging off my fucking head, my pasty white skin a rich red totally covered in blood, and wrecked those little degenerates.
I've had to learn that when something should probably hurt, that I should pay attention. A good portion of people who have this die, because of what you said, they don't know they're hurt. My doc is convinced that it was the body hardening from the early start in pretty hard core martial arts, and the actual hardening exercises my masters had me do, kept me from incidentally killing myself.
F'ing Army and another agency put the condition to use; that's for sure. Which has made for an interesting life.
I don't get to talk about it much. Thanks for the platform to vent a bit on it. Never realized how good that would feel.