Connecting PAS to Cam for Off-Width

because it allows you to bump the cam without pulling up the weight of the rope

It also helps keep the rope in a less annoying position / not getting pinched between your leg and rock while trying to bump. 

As long as you don't hang on it. . .

This is a great idea! I hadn’t ever considered this. 

Its a common OW technique that allows you to climb on "top rope" or at least semi safely through OW sections.  Also lessons the number of big cams you need to carry depending on your safety tolerance 

Looks like a good technique to me. I've had a cam come out/uncammed when doing this and if you drop it without the PAS then it's gone. Which is terrifying to think about. 

I haven't seen this video but we once used it to protect the anchor. A friend did this technique on TR, following on multi-pitch, hanging belay. The circumstances are hard to explain, but Bestie was about to be taking some whips.