That’s great, convert2010. Really great.
I am wondering if putting a simple loop on the end of the amsteel and then using, as someone else mentions, a toggle (a tent stake, a butterknife, etc) on one side of the door would work…might distribute the force more than the knot, and no tying method. But, your knot idea does work as it stands, indeed. Door opening inward or outward probably wouldn’t matter if the hinged side is used for the knot.
You might want to put the word “hammock” in your video title… as the title is now, it’ll never come up when someone youtube searches hammock.
Hey, idea—could the amsteel simply be tied around the hinge itself. i.e. open the door, thread it once completely around top hinge (all the way around it from top to bottom), and then shut the door?