IMHO .... if vertical jigging it might make more of a difference, which is why many use a loop knot or clip on their jig. Me, personally ... I cast & slow retrieve with jigs most of the time, and I tie a Improved Clinch knot to my jigs. I retrieve slowly, so the line is rarely straight/taut from rod tip to jig. There's a "under curve" (bow) in the line from rod tip to water's surface, and the weight of the jig causes a "over curve" (hump) in the line underwater as it falls back towards me. That generally levels the jig, even if the knot is centered or slightly forward of center of the jig eye. I've always done it this way, and I've caught Crappie all along the retrieve ... from splashdown to right at the surface as I'm preparing to lift the jig out of the water for another cast.
To my way of thinking, the depth & speed part of your presentation is the most important part. Everything else is "fine tuning".
... cp