For my own peace of mind, I decided long ago never to book an itinerary flying with any airline with a connection of less than 1 hour domestic, 2 hours international. If delta.com gives me one with an absurd connection, I move on to another itinerary (on DL or another airline) that gives me what I require. And in 6 years of relatively frequent business travel, I've never missed a connecting flight.
YMMV
