So, let's use an example. I'm innocent. The t room door opens, so I walk in. On the floor is a spray of player X. Is this valid reason to kill player X, because other than this i have not seen him in the t-room.
No, because it could have been sprayed when he was a T in a previous round However, if it is the first round of a map, it's still a kill on suspicion I'd take it
No, because if I'm at T in round one, spray in the T room then you go in there in round two and see it, you'll be KOSing me for something that happened last round.
Would it be ok to kos on this if you cleared the sprays each round(like in the preround where there is no way for someone to spray) or is the clear spray function not reliable enough for it to be allowed?
This is something I'm not well enough versed in to answer about, @Opalium should have an answer for you.
I think it should be kosable only if it happened on the first round. Any round after that, its not kosable.
No, because clearing sprays is a client side action. Only you can see it. This makes it unreliable, as we cannot be sure if someone really did clear them or not before KOSing like that.