I have a 40 minute connection HNL-DFW-PHL in a few months that was booked on aa.com. I don't see anything on aa.com stating a MCT for DFW on domestic to domestic, but it seems like that's a little too tight. Yes, they can put us on the next one 2 hours later if we misconnect, but I'd rather not role those dice and get stuck in a middle rear seat.
I found this in the Wikipost at the top of this thread (I have no idea when this section was last updated):
MCT: Minimum and reasonable connection times at DFW
Q. What is the domestic to Domestic or Domestic to International Minimum Connection Time (MCT)?
The minimum connect time at DFW, Domestic to Domestic or Domestic to International, is 0:50 minutes. (Remember, International flights may begin boarding 0:45 from scheduled departure.)