Do you guys use a loop knot to attach your fly to the tippet?

I have just started using this knot, seems to give the fly a little more action if it?s a nymph. Possibly a better presentation for dries.

A very successful guide I fished with recently will only use a loop knot to attach a fly.

Perfection loop :
https://m.youtube.com/watch?v=YCDolG7dHtQ

I use this one
Non slip loop:

https://www.netknots.com/fishing_kno...slip-loop-knot


Scg