600 x-ray checks could be done in one stage race. They don't drag the machine around everywhere, and that's just for WT races. The UCI and the NGB's rely on the iPad magnetometer and the iPad FLIR camera, something that's cheap and portable. TT bikes are jigged, either mechanically or electronically, but only a small part of the regulations are checked. It would take way too long to check everything. I agree that the climbing bikes, especially the ones that a rider swaps during the race (a practice that I totally disagree with and should not be allowed) would be the primary target.
That video had a lot of drama and not a lot of substance, but hat's off to the students for developing a working prototype. You wouldn't need an x-ray, magnetometer, or FLIR to detect that wheel, though. The weight difference would be obvious.