This happened me today, I reported a guy for cheating for just knowing I was there, then I realize he was a console player) And googled this. I heard about this earlier about they can feel that their aim slows down, he just went out from his cover and killed me when I was sneaking up on him (I used a drone to pin point his location)
He killed me twice using this tactic which is very unfair. At first I was thinking he was using ESP since first time he shoot like crazy through a bush but missed a few shoots then jumped out and made the final kill. Second time he was behind an another cover and I am pretty sure I was not spotted (no drones, no nothing)
It is useless if you can't use tactics like sneaking up to players when they are behind their covers and can just use their ADS to scan for other players.