I have have been using the first knot for over 35 years for all manor of things.

I first learned it as an early teen from my father. We used it to secure the tarp over the top of our boat after we pulled it out of the water and towed it home. Never had a rope come loose even with the tarp being flapped by 70+ MPH wind on the drive home.

Putfile is a pretty common site and other than making you click through a bunch of pages of adds to get to the download button it's pretty harmless. If you just watch it a the main page and don't try to download it, you don't have to bother with the adds.

I've also used the 2nd knot he showed from time to time - it's pretty handy.

My knot repertoire is pretty limited and I can't rate them against all manor of other knots other than to say they've worked for me.