In the video (go to 7:41), it shows Alaphilippe's bike in stage 1 seems to have locked the front wheel (I don't think I've ever seen that happen to a rim brake wheel unless the wheel is pretty much taco'ed). I'm wondering if Alaphilippe crashed and caused the disc to bend and thus causing his front wheel to lock like that? Did a crash knock the brake caliper way out of position causing the lockup? Or did the front brake just lock up first (for whatever reason), causing Alaphilippe to dismount? Alaphilippe's jersey and bib didn't have any rips or tears on them, so I don't think he crashed, so it could simply just be a brake issue, me think.
Then the mech from the sag car tried to remove the skewer with a power drill (ugh what?) and that didn't work either.
Then at 12:33, one of Lopez of Astana apparently locked up his rear wheel in a turn and slid out. Would he have locked it up if he was on rim brakes? I thought disc offer better modulation and feel?
Once thing for sure, changing wheels with disc is a lot more complicated than good ole rim brake wheels. And I thought disc brake is supposed to shine in this very condition of stage 1, ie, wet. But as it turns out, stage 1 was filled with crashes.
Perhaps guys have forgetten how to ride in a peloton after a long layoff? let's hope the rest of the Tour is better than stage 1 carnage!