i love calligraphic swash
and, as it is often a monoline form,
it can translate to acceptable mat knots 
here are a couple of drafts.
calligraphic ornaments lack formulaic description,
so i’m not familiar with any existing nomenclature,
so for now it’s ‘round mat’ and ‘long mat’.
many a half hitch feature in the mats,
when in calligraphy we would’ve just called them ‘loops’ 
