Getting used to properly loading a fly rod has helped me a lot with understanding how a rod loads and the dynamics of casting in general, regardless of what kind of gear I have with me that day. A heavy 8wt fly rod, for me, is by far the most exhausting because my technique is still nowhere near as good as it is with conventional tackle. Still, if you think about it, regardless of tackle, the more work you can get the rod to do, the less you have to. Part of my goals for this year is improving my casting. Part of that, for me, is mechanics/technique, and another big part is cast selection. For example, while I think the two handed overhead cast is better than the one handed overhead cast for maximizing distance and throwing heavy baits, I'm going to prefer a roll cast (with casting gear) most of the time because I can do it with less fatigue, with better accuracy, and smaller splash regardless of whether I'm using one hand for something close, or two hands for heavier lures or more distance. This whole efficiency thing, for me, is huge because it minimizes the effects my back and neck have on my fishing over the course of a day and whether I'm good for a weekend or seized up in spasms after 4 hours.