Nearly dropped a 40 ft red oak on a fence in Tulsa last week, my notch was the whole problem
I used to cut a wide open face notch on every takedown because that is how the older guy on my crew in Tulsa showed me, and I kept getting trees that slid off the stump early. Switched to a narrow 70 degree notch with a proper hinge a few months back and the control on that red oak was night and day, it sat down right where I aimed it. If your hinge is breaking before the tree commits, check your notch angle before you blame the tree or your saw. What angle are you all running on big hardwoods?
70 degrees all day on anything big enough to hurt you. Wide open face is fine for softwood or small stuff but on hardwoods that hinge closes too slow and the tree gets impatient. Sounds like you already figured that out the hard way though.