We have flown thru ATL.
We have done this with short layovers, like about an hour.
Two things.....
If you are flying check-thru domestic... (one ticket, same airline for both flights) You probably will not have to change terminals.
Should probably be a fairly quick walk over.
No time for stopping, snack, etc...
If you are booking this as one ticket/trip on one airline, they should be aware of the necessary layover time, and not book flights with an insufficient layover. When you pull up the flights, do you see the lay-over FLAGGED in any way?
International flights would require riding the tram over to the International terminal.
Secondly, I would hope that the airline knows that passengers are due from one flight from the next....
So, they should not close the gate if they know you are there somewhere, heading to the gate to board.
One small thing....
The shorter the layover, the shorter the time they have to get your luggage transfered onto the plane.
Thank goodness our luggage followed us, with a fairly short layover, on our last International flight to the Caribbean...
But, even with a longer layover time, it did not make it onto our plane from ATL onto the short flight home?????
I think it was DELTA.