The difference between fog-clicks, and delayed fog clicks.
It's come to my attention that there is a misunderstanding when it comes to Fog-clicks, basically we have users posting a ban request, and they just paste all the fog-clicks onto the thread. This method of reporting is very sloppy, and it makes catching & banning the map hackers much harder for the Admin's viewing them.
Below I will explain the fundamentals regarding delayed fog-clicks.
Delayed Fog Clicks - When a person clicks a hero before he enters into the fog - once that hero disappears into the fog, the selection circle remains on it. This happens often when the hero you are viewing from dies - Quite often, the user usually selects the hero that killed them. When their hero dies, they will usually not click anything for a while, and thus the click remains on the opponents hero, even when that hero enters the fog (will last until next click), so the program counts it as a fog-click when it actually isn't.
Below in this image you can see that Invoker selected Barathrum at 13:25 game time, before Barathrum entered the fog, but the click won't appear until 13:26 game time. Because of some delayed process in the DotA map.
http://prntscr.com/223zqj
Now as you can see one second later, at 13:26 game time, it shows as if Invoker (wasginnyl2) selected Barathrum in the fog, when he actually didn't, the click was dragged into the fog, just as he clicked him before Barathrum entered the fog. It's not counted as Map Hack. The click should appear up to 2 seconds max after the hero entered the fogged area.
http://prntscr.com/2240b2
Also note ; Blatant fog clicks (i.e. fog clicks that occur in an area of fog nowhere near allied vision) are conclusive unless it is the respawn selection bug. (Meaning fog-clicks that were selected nowhere near any vision of the hero, are sure signs of accurate fog-clicks.
Fog clicks that occur on the "border" of allied vision can be bugged, as the fog system is done in 'ticks' and hence delay or ping could make the replay seem like a fog clicked occur.
I hope you fully understand the delay fog-click process now.