Really informative comment on that video:

"Nice video. Couple of points: 1: As per the title of your video, its worth emphasizing that these are tension indicating bolts, not torque indicating bolts. 2: With any bolted connection its the tension that is important. Whilst torque and tension should be correlated, that relationship varies considerably from bolt to bolt, lubricant to lubricant, hot to cold, state of corrosion etc... 3: So a bolt torqued to say 100NM may well have a tension variance of over 100%. The result is that bolts are often over or under tensioned, which can compromise the entire bolted connection. 4: Bolts like this (I've personally used Rotabolts, which are similar in concept but in my opinion better as they rely on a mechanical indication rather than a subjective color hue.) are very useful for certain applications, for example, sub-sea connections where divers have limited time and feeling, and sea conditions affect the bolt lubrication. 5: Other uses are for ensuring correct bolted connections on sensitive flanges, again offshore and sub-sea sees a lot of this. 6: Bolts like this are, in summary, brilliant for when you need a good quality bolted connection with correctly tensioned bolts. For most applications however they are unnecessary. Keep up the good work! :-)" - drawingboard82

Side note: youtube mobile when I tried to copy the comment wants me to sign in, to just copy a comment! wtf youtube! I just opened it in newspipe instead and copied from there

One thing missing here, but talked about (albeit not very clearly) in the video is that it’s not even a tension indicator, but rather, extension indicator. As long as we are in elastic regime, tension and extension are the same thing (Hooke’s law). However, once you go beyond it, tension goes down even as extension goes up. This is what the canuck meant when he talks about people tightening the loose bolt by giving it extra tweak, around minute 3:40 in the video. Once you leave the elastic regime, the bolt holding strength is permanently reduced, and by periodic tightening, sooner or later you’ll see it yield altogether.

When you said "some crazy canuck", I immediately knew it must be AvE

Knew it was AvE just from 'crazy canuck'