Agreee with most of the above. Everyone should always try and cover their own rear and not expect others to. That said, I'll try to give checks but my vox isn't working on my main computer and trying to type out warnings is sometimes impossible if you're engaged in your own battle.
What's the "check six" button? I actually gave one of those text check sixs to someone by accident not long ago but wasn't sure how I did it. I hit the wrong key but was so busy I wasn't sure which one it was and saw a check six, with my name on it, in the text message box.
That may, or may not be something I could do while I'm in a fight.