They don't disqualify people on the road. I had bad knee trouble in 2019 and was way behind where I should have been and was there when they closed a couple of controls. They were running around seeing if anyone needed their control cards signed. Obviously anyone that needed their card signed was hors délai.
I don't know why you wouldn't do the whole ride the way everyone else does though, the bureaucracy just isn't that bad and the controls are only every 100km. And the food is good (in the context of riding long distance).