Again, though, you've got ask yourself if it's worth it.
I tried this one.
Using threads I could not get it to work. Because of the tighter spacing of the mains the thread would no pull through easily, so I adapted the "trick" and used 2 leftover pieces of string. I tied them into 2 intertwined loops and weaved one end. You can now used the weaved looped to pull it through and use the other loop to pull the first loop back again.
It works great, but.....
It only works in one direction.
When I'm doing a manual weave on a "full-cross", so weaving all mains, I need about 9~10 seconds max, 7~8 if it goes perfectly.
With the string loops I have to put the thread into the loop, pull it through, take it out, and pull the loop back. This takes 3 seconds max.
So I save 7 seconds max on about 11 full-crosses. So ((11/2)=6 times 7 seconds) 42 seconds saved total on a total string job of about 35~40 minutes (I take my time, and even pull out strings if the outer crossing is not to my liking).
These 42 seconds saved are somewhat less because I lose some time on an occasional interference with my string (you have these loops hanging from the stringbed).
So timewise, it's not something which helps a great deal. The only reason for using this trick for me (I'll give it a few more tries) is it saves 50% of the most tedious activity during stringing. I do not like the weaving part, and just pulling the string through feels good