Some knot discussion from a guy that used to work on ropes courses.

This is what you would generally attach to a climber. It's a very basic knot. Strong, and as you can see, the loop sticking out is static (you can't make it any tighter or looser by pulling on it.

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Now, in that knot above, there's some trailing cord

Normally, this tail is used to form a backup safety knot. but you don't want a big mass of rope, so generally two or three loops max

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Now, here's the rope from the Nascar image

A key feature here is that you can tell this isn't a "stopped" knot - the rope comes all the way through - this is so that when weight pulls, the hole in the rope gets tighter.

It wouldn't make a good "pull handle"

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