disregarding my previous meme, i have a legitimate answer maybe.
When i mained demo man, it was less efficient for me to track someone than it was the just keep my crosshair still when i wasnt firing. This was because i wanted to watch for when the enemy was changing their direction (strafing), and base my flick off of that. It was easier to do that when i wasnt moving my crosshair, because then instead of dealing with 3 factors (them moving, my keyboard, +my mouse) i was only dealing with 2 factors (my keyboard and them moving). This habit transferred over even as I play scout, where when im not actively shooting i essentially ignore where my crosshair is. This means when I aim I make extreme aim adjustments, and often have to readjust at the end of flick (like elacour albeit a bit less of extreme).