"Polytetrafluoroethylene (PTFE) is a synthetic fluoropolymer of tetrafluoroethylene. Being hydrophobic, non-wetting, high density and resistant to high temperatures, PTFE is an incredibly versatile material with a wide variety of applications, though it's perhaps best-known for its non-stick properties."
In plain English, it's a type of lining for woven/braided hose. It's supposed to be super tough but IMO kind of overkill for what most of us do here. It's a two-part hose since it has the lining and exterior and requires specific hose ends/fittings. It's also expensive, probably more so than your normal -AN type stuff.
I looked back through the thread, I don't see any PTFE hose used anywhere. The power steering hoses might look like it since they have "custom" fittings but to me they look like regular p.s. hose just with nice hardware.
I use
Aeroquip socketless hose which does not have a lining and uses
one-piece barb hose ends. Been using it for years, never had a problem with it. Fairly light and looks unassuming too.
Carry on.