That's an excellent video, damn good find, but it's not a case for nylon vs. dyneema, it's an illustration of the importance of elasticity to shock loading.
It's pretty well understood that Dyneema doesn't stretch and nylon stretches a lot, polyester (lifelines, tenex, etc.) is somewhere in between. Nylon has problems with UV degradation. Depending on the weave and the loading, nylon doesn't necessarily recover completely after stretching so cycles to failure is more critical. They're just different.
Stick a dynamic rope in the system and all those numbers will change dramatically, the longer the rope in the circuit, the lower the numbers. Without a rope in the system a fall factor of 1 or 2 would do serious damage to your body before the sling broke regardless of material.
I don't use dyneema for handling significant shock loads but it rocks for getting trees off houses and lifting with MA. I do use those skinny runners for light shock loads. I have a little kit with a carabiner and two slings, a 60cm and a 120cm. I can tie off most limbs with it quickly so I don't have to cut and hold small stuff over targets.
Most arb ropes are polyester, not nearly as stretchy as nylon but super durable. Polydyne is a composite double braid with a nylon core and a polyester jacket and it stretches like crazy but it also recovers fast, sucks for lifting but it's sweet for catching chunks.
I made a tether for my CMI Expedition Dual ascender with HTLL, it's nice and clean but I still back it up with 5mm tech cord. Like Carl said, shock absorption on a line that short is pretty insignificant with any of those three fibers.
I also used the HTLL to rig up a really sweet hammock anchor between two trees for a customer. I like it but it's limited and kinda pricey, 16 strand technora is cheaper and does more different stuff.