The trucker's hitch is a classic. Your inclusion of the round turn and two half-hitches is a nice bonus. Both are knots everyone should know and posting the explanatory video is something of a pubic service.
The trucker is structurally a field expedient 3:1 pulley system used, in this case, to tension a cargo hold-down. The same basic design has other uses. It can be used to haul cargo bags up a vertical wall during a long climb, used to tension a line across a waterway so it can be used as a safety line, or over a crevasse as a bridge. Rig two or three of them to make transit of numbers and cargo go more swiftly.
You featured the use of a slipped figure-eight knot to form the loop. It works. In fact if the line your using is not going to be reused, like when you use the line provided as courtesy by the hardware store to tie down your purchase, it has absolutely no down side. On the other hand it is possible to tension that particular knot to the point where it becomes quite hard to remove. Resort to a marline spike, possibly a knife, might be required. A consideration if you are reusing the rope.
In military mountaineering, as of the mid-70s, the basic design incorporated a butterfly knot to form the pulley-loop. A knot that is singularly impressive and seemingly complicated but, once you get the hang of it, shockingly simple. Unfortunately the butterfly shares the slipped figure-eight's tendency to bind up semi-permanently if highly strained.
For a time I used a modified slipped figure-eight. One where a second half-turn is made before the tuck used to form the figure eight. This extra bit prevents the knot from binding and greatly speeds breakdown for reuse. It is an option but I'm so used to figure-eights that I often forget the extra bit.
More recently it came to my attention that the US military teaching on bridging has shifted from using the venerable butterfly knot and gone to a slipknot with a half-hitch. Admirably simple to tie and not prone to binding it has a lot going for it. Just remember to start your grip when forming the slip-knot closer to the working, instead of the standing, end. Lay on a half-hitch to lock the loop and your good.
Of course all this is knot-tying inside baseball. A bit esoteric for most users. Any of the variations on a trucker's hitch will work. The fine gradations of form and function get lost.
More practically it has to be noted that the efficiency of this field-expedient pulley system can be greatly improved by hanging a carabiner on the loop and using it as the pulley. The friction and wear and tear on the rope with a carabiner is much reduced. Using a carabiner, or better still one on each end, it is possible to loop the pull-line through again and increase the mechanical advantage from 3:1 to 5:1.
Noting that 5:1 is about as good as it gets with such field produced setups because friction rapidly overcomes the advantage. Even at a relatively mild advantage of 5:1 you may need to chase the slack around the multiple turns as sailors used to around dead-eyes to keep the rigging tight.
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