I've seen it happen once. This was around 1985. I was riding in a small group and we were nearing the end of a ride where we would often crank it up if we had any gas left. We were going pretty fast but not really sprinting, maybe 28 or 30 mph. We were drafting each other when the guy in front's front tire came off the rim! We were on a straight stretch of road and he managed to keep it upright as he rolled to a stop on the rim. The tire was still inflated and it just stayed right between the rim and the fork crown and off to the side of the rim at the bottom. I remember that the glue was not tacky at all. No telling how long he rode it like that before it finally came off. The glue must have just completely dried up or not been adequately glued to begin with. That's kind of stuck with me all these years.