I believe Chaos is correct at least as far as 40 being to high. I played a Necro that only got to 50's. I know for a fact that I had a pet that DW's while I was XP kiting in DL. Not exactly sure what level that was.
As far as quad's... that's a Special Attack in the NPC_Types Table so DW doesn't enter in to it.
Ideally I think this should be swapped to a rule, as some purists will want to have it "The it is on Live" ... which probably changed at least once per expansion...
others will not want to re-balance the NPC's
others still will think it's awesome that they can change it.
my 2cp... for what's it's worth with this exchange rate