Sounds entirely plausible to me. I've tumbled through my lines many many times during a very hard fall. With a leash it would have been disastrous.

I've even had my board tangle by the foot strap on an outside line, dangling 20 feet over my head as the kite launched ... I had to pull hard on the opposite site of the bar to keep my kite from going into uncontrolled kite loops, board still attached. That was scary as hell.

If it can happen, it will, eventually.