Today i tried with my "old tool " , i.e. one of the two thinner guitar chord (i can't remember, B or G as you said maybe, i am a drummer ... ) rolled on a champagne plug as a handle . It worked far better than what i remember from my last experience :
Certainly thanks to its coating that gives some rigidity (my previous 0.8mm dyneema was from land power kites since not existing for kitesurf at that moment, pure white without any coating).
I was easily able to splice it on 10cm , so it is not a challenge nowadays.
way back in 2003/4 i did a home made test on the Q line I was using,
I had a spare length of standard Flexifoil line and a length of standard Fone line and the same with a length of standard Q line.
I set a shackle up on a fixed post and fixed each length of line in turn to the shackle and the free end to a kite bar.
I gave a very sharp pull to each line, holding the kite bar as normal with both hands,I was trying to snap each line.
Imagine my shock when the 2 standard lines snapped easily without full effort, I kept repeating this test as I was in disbelief that they snapped so easily,
the Q line was almost unbreakable and held strong for many attempts, I thought the bar would break first. the Q line was fixed to each end with a simple figure 8 knot at one end and a larks head at the other.
I intend to repeat this test as soon as my new Q lines arrive this week or next, I have my North lines to test along side them.
How do Q lines handle rubbing from loops or back rolls? Most of my lines get frayed pretty fast from this.
Jeff Howard did a video on Q lines and all that was needed for the ends was a figure 8 knot, no splicing of sewing needed.
Q-power handles this extremely well - as in it won't be a factor at all.
I had Q-power Pro about 14 years ago ant then its only weakness was that wrapping it around the bar would gradually develop many areas where the inner core would show under the outer sheath due to the bending. Was never recognized to affect line strength at all - Purely cosmetic. I retired that set just because come on - 10 years is enough for anything. But if would still fly fine.
I've been using the same set of Q-power not pro (thicker diameter) for past 4 years and they look new like the day I bought them, no impact from wrapping. I don't know if the new pro is the same.