I'm not sure how to say this, just my opinion I guess. All those 'thingies', loops and such might be fine for delicate work but when I really any line the loop will not survive too long. I think it's a hinging problem mostly. I put a loop in my leader and just tie my fly line to it. For me, loops just add to 'things that can go wrong'.
ooops, John, as you know I am not a fan of the Fail-knot either unless just for tiny troutie stuff where it has to go all the way back onto the reel to land a fish.
I never tied one that was right. If it was tight it cut the coating; if not tight it slipped off; if perfect,,, a big fish would pull the coating right off the core. Nope, sorry, mostly,,, knot for me.