Am not sure about using tautline hitches in the kind of weather in Ryan’s video. Would expect the cord to ice up at the knot. But like Paul, am not enthused with the popular Lineloc 3. Am also not enthused with running the cord twice through the same hole, or with bar tighteners that have been great for a lot of applications, like making pulleys for webbing, but not the apps they were intended for.
But there are all kinds of acetal plastic tighteners out there, a number of which I looked at when working on a clamshell tent design posted on another thread last year. Found different ones on Amazon and some other sites.
Paul’s post on the thread linked in Rene’s OP focuses on the ‘knife edge piece of plastic’ inside the lineloc LL3. That always bothered me too. The LL is bulky, yet has some tiny plastic parts. Don’t see a need to use grosgrain or twill tape, when 1/4″ lace will do, and take a smaller tightener. The Dutchware tightener shown in Chris’s post near the beginning of this thread looks a lot more solid to me, altho needs 3mm cord – yet he says there are other smaller ones: https://dutchwaregear.com/product/line-lock-hook/
So it looks like ordering the least bulky yet strong ones available, stringing them with some spectra core cord, and break testing. Will have to think of a way to generate enough force to break them. Maybe a small hydraulic jack set up, or my farmer’s jack that is tall enough to set up to stretch a foot or two of cord.
I think there are sleeker and stronger line tighteners out there for 2-2.5mm spectra core cord. There was a thread on BPL a few years ago with names of arborists selling spectra cord at lower prices; don’t have a link, but maybe someone will be able to post one.