1. I don't touch my line.
2. I will swap the same exact 1/2 oz jig with superglued trailer and the same reel to different rods.
3. Depending on the rod I am using I can definitely feel different things or vibrations fishing in the same exact spots. I will often cast to objects where I can see my lure so I know it's in the same exact area parallel to the bank or near certain patches of grass. I will cast my jig on top of a ridged culvert that connect the lakes and the bumps feel different.
4. I have watched peacock bass peck, pick up my lure or blow on it to get it away from them with certain rods and felt different things, doing things the same exact way.