The distance between the D and E stations is quite a bit shorter than the other stops. Noticed this a few months ago when I had to get from the end of concourse A to the end of concourse E with about 15 minutes until departure. Even though I jogged a good bit (other than the train ride), it took me about 14 minutes. Unfortunately, they had already closed the door by the time I arrived. I suspect I could have beat the train from D to E if I had got out at D and just jogged to E.
Are you talking about DTW which only has A, B and C concourses in the Delta terminal?
Bob H