I fly delta more than any other airline. The app is great you always know if your bags made the plane or not. I did have our bags 24 hours behind us on a trip home in 2017 from the Cape. But we were late at airport and delta sent me a message saying my bags were not going to make flight and were going to be a flight behind us.
So worked for us. I do long lay overs when i have to switch flights. I believe this is a great help with bags. Plus it gives me time to relax have a drink and a not be pressured to hurry and try and make a tight schedule. I look at it all including flights as an adventure !