Notwithstanding the above, and I agree in large parts with what orbitmic and others have said and in fact have previously on one occasion spent longer in the MIA immigration hall than on the plane (during a US govt furlough), since the start of this year I have been through US immigration at MIA x2, JFK and IAD and have not waited longer than 3 mins (admittedly I was in F and so amongst the first off the plane on all of those flights). In fact, on only 1 occasion was my passport stamped and on only 1 (different) occasion were my electronic fingerprints taken. The new ‘light touch’ approach seems to be working and I am starting to wonder if I needn’t have bothered applying for GE for which I have just been conditionally approved.
I can’t speak to DFW but will be connecting through there with my family in the summer so have read the above with interest but I suppose my point is that it isn’t all totally bleak!