I built and used those old Baker styles a lot back in the day. Made them for the most part with a welder and angle iron.

Only time I ever had one fall, I was already on the ground watching my buddy climb down with one. He was bear hugging the tree and climbing and at the point of standing on the stand to regrip and dropped something he was holding behind the tree while climbing. That hit the back that was gripping and everything and every body just started down like you cut the cable on an elevator. Dropped about 10 feet and the bite in back hooked up again and came to an immediate stop. He was still standing there kinda not really gripping the tree and everthing was exactly the same only 10 feet lower. Every thing but the look on his face and that was totally white, just long enough for us both to take a breath and start laughing. What else could you do? It was the ultimate test on the stand integrity, nothing broke.