I believe you want to have the jig moving more or less "freely" on the retrieve, drift, or troll. This can certainly be accomplished using a loop knot of some sort. However, I do not like the idea of the eye of the jig moving freely against the
inside of the loop knot, mainly for a concern about abrasion of the loop.
This can happen! Years ago when I first started trout fishing, I always used a loop knot. Then one day I hooked into a decent bass and played him for a few minutes. The line went limp and I pulled in my loop which had broken at the end of the loop. True story.
I still believe a free moving jig head best allows your bait to act in a more lifelike manner - as opposed to a direct tie. So, I tried some different snaps and finally arrived at the best solution for my problem. They are called "Snap Hooks", which are sold at Jannsnetcraft and manufactured by Mustad. The are
light spring wire clips that are small, yet allow full freedom of the head during most presentations. You tied directly to the clip. Here is the link:
Mustad Snap Hooks. Easily change flies without tying
They are designed for flyfishermen to quickly change flies while wading. (That speaks volumes for their lightness!) I've been using these snap hooks for many, many years now (the size #2 works well with 1/32 - 1/8 oz. jigheads) and they give me the confidence that I'm presenting my bait as realistically as possible.
These hooks also allows for
quick change up of jig heads should that be necessary. I've caught a ton of crappie, perch, bass, trout and pike using this simple snap. I see no downside. Just my opinion, but it does work well for me. Tight lines Folks!