He goes into -- from what I've seen -- how you shouldn't even mix 'n match caps when you disassemble a new u-joint because you'll disturb the grease quantities (sometimes the grease stays in the cross, sometimes it sticks to the caps), and how to use the different thicknesses of snap rings to get the joint tight and centered (only a minority of joints even come with a selection of thicknesses)
I've then watched vids of the big driveline builders like Tom Woods. They throw all 4 caps on the bench, throw it together and grab any cap for reassembly. I also never saw them worry about clip thickness, but maybe it just wasn't shown. If Tom Woods were experiencing excessive failures in u-joints I feel like that would trickle through the aftermarket community.
I think the aforementioned vid series is a great example of things that look good on paper and aretechnically correct, but the concerns of reality don't always match up with the priorities of theory.
