i think of the double eyed split tail friction hitches we
use as all very similar; this giving a key to easily remembering them.
They all employ a top coil (4 uninterrupted turns around host lifeline)
that will give pretty sure stop, but too powerfully so might bind. So we
precede them with another choking grab (except VT family uses a gauntlet
of braids to bend lifeline like rappelling rack to not pass full loading
to the coil) to limit loading to the coil and keep it in it's productive
powerband of slide and grip without seizing.