i'm sure you've all experienced the same problem.
Yes indeed. Interesting question that involves several tradeoffs:
1. Does the benefit outweigh the trouble of tying the knot?
2. The less it slips, the more it might constrict and cut circulation to the end of your fingers. For instance a constrictor is super fast to tie, but it will be uncomfortable.
On account of both of these tradeoffs, I have given up.
But I don't care, eight months ago I started to use "brushettes" every time after I floss. If you haven't used them, you'd be amazed at how much stuff they pick up
after you have already flossed. And for the first time, at my bi-annual cleaning, the hygienist told me that everything looked really good. That was really great to hear as usually they tell me I can lift up my game, which left me confused as a regular brusher and flosser.
Regarding flossing, I just make a few turns. If it really slips, I guess it's time or to floss without toothpaste in my mouth, or to invest in another piece of floss.