My wife and kids got to enjoy the beautiful MEM airport for almost 7 hours last week. They just missed there connecting flight (thanks to MX delay on the RJ coming in and MX delay when they tried to leave). Their connecting plane (same plane) also MX out and left late. 5 more minutes here would have had them avoiding sitting in MEM for 7 hours and wouldn't have changed anything down stream as the flight that left them behind was 30+ minutes early. They arrived to the gate and watched the GA walk down to move the jet bridge.

So my attitude is if you have already taken a mx delay, why not hold that extra few minutes to get the connections on board. The situation as I described costs nobody anything and buys good will!