I went into overwatch and replicated the same scenario on PC. I completed the process and it resulted in a change from a 5000 mouse sensitivity index (1000dpi x 5 sense) to a 2000 mouse sensitivity index (1000 dpi to 2 sens) - from a 9.875" 360 turn to a 26.5" 360 turn. In the training room I can already tell my aim is much smoother and more accurate, however, the sudden decrease in turn speed is definitely going to be a big adjustment. Luckily I already have a 16"x18" moousepad and have the space to move my arm around. Despite knowing that the sudden change will disrupt my short term performance in terms of being adjusted to movement I know that it will be an investment into future performance that will have a large payout. Thanks for the tutorial 
that sounds like a pretty good sensitivity now, mine is slightly slower (something like 45cm per 360°)
give this turnspeed a few days and you will ask yourself how you ever played with anything else!

for some OW characters accuracy shouldnt be your main target though, you might want to go for a faster sensitivity there and sacrifice some accuracy (eg dva)
Nice tut Od1n.
Do you use the same methodology in high AA games?
The concern is breaking through the AA bubble into the hitbox, which can get trickier at lower sens values when AA is higher.
I tend to optimise my aim in say Destiny 2 at 3200 DPI, then bump up the DPI to 3600 to help with cut-through into the hitbox. Essentially that's the same as increasing sens by 12.5%, but it's just a quicker way for me to get there.
I also found that I needed to roughly halve my Overwatch sens compared to almost every other game I play, so it'd be interesting to replicate this in another title.
Great approach nonetheless, I'll give it a crack 
yes this is a valid point indeed, with slower sensitivities aim assist can become an issue
i usually counter this by either deactivating or reducing the aim assist if the game allows that (eg use aim window 30 in Overwatch) or by adding in some smoothing
the smoothing helps to get into the aim assist bubble without having that barrier trying to push you away or stall your mouse for a slight moment
another great way is to actively aim by moving your character as well
this is what i do in overwatch, when i attempt to target on an opponent i usually adapt my movement to that so my WASD breaks my cursor into the bubble (or out of it if needed)
it takes some practice but is really effective
(alongside using 30 aim window in OW)
this is how controller players aim, if you watch the better pad players youll see how a large share of their aim comes from moving their character
the aim assist algorithm is tailored around those input patterns so adapting your keyboard or nav movements to that is really beneficial
this is why people playing with a nav usually say they have more aim assist or struggle less with the aim assist bubble as they automatically use their analog stick to partially aim or stay on target
Great tutorial Odin. Request todo one for Fortnite and also share more gameplay!
fortnite tutorial is planned but ill most likely do an overwatch and ballistic curve one before that