That's what they told me
Yep. I never saw. Never even heard of anyone who had really experienced it. BUT, they told me that's why the "max speed 45 mph" label was on the dash when I picked it up. "They" said that under panic braking without ABS, the 900 series truck would nose over. The ABS tag went on, the "max speed" tag came off, the CTIS worked, ta-da!
Of course, my LT also said that the "overspeed" light on the dash was just a way of scaring drivers from going too fast. No amount of evidence could convince him that cruisiing 70 mph for the entire 5 hour trip was actually damaging tranny parts.
During training with the M35A3, on an icy airport, I purposely stomped on the brakes to get it to stall out, which it did 2 out of 6 times. Never any problem braking otherwise.
EDIT:
After the ABS went on, my motor sergeant (full-time mechanic at the maintenance shed) said that flipping the switches in reverse order would somehow disable the ABS and allow the CTIS to work better, but I could never remember which way. My CTIS always seemed to work, with a few hisses and spits from various valves in the cab, and I never worried about ABS. Never came close to a panic stop.