Top write up!
All of it very true.
Unfortunately most DJ's I've found always talk the talk, however when it comes to the crunch on the decks - party's rockin, place is crankin - they always get too excited and just start turning it up and up every track until they're redlining the fuck out of the mixer...
Doesn't matter how big the system is either - I've set up masses of booth monitoring on stages and in clubs before, and it doesn't matter if there's thousands and thousands of watts 2m away from the DJ, doesn't matter if the PA is 10 times too powerful for the room, its still not loud enough and the red light always seems to show itself...
I used to be a total gain nazi, but now I'm just over it - I set the limiters and hey, if you want your set to sound like shit, go right ahead. Of course I'd step in if things went too far and equipment was going to get damaged though.
The Gay scene DJ's and the older more experienced guys are fantastic, never had a problem with any of them, they totally understand the gain structure thing, and if not, they just know to keep it in the green. The younger ones (that always seem to have the attitude about it too) on the other hand... no idea.
Anyway, point of this ramble:

KEEP THE FUCK OUT OF THE RED!
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