Wow!
IMHO, I believe that one of his founding assumptions, that Express and Mainline aircraft would experience the same or similar changes, is incorrect to a significant degree, for several reasons.
One, the easy access to/from 18L/36R to the express ramp. A factor utilized by SWA to minimize taxi time. The less the taxi time, the less time there is to manipulate, if that is the pilot's intent. I likely missed it but perhaps the Dr. could factor in the percentage of Express departures north through south vs total, highlighting those Express taxi times that would be more likely to correlate with mainline. Also, I don't see that the broken concrete on the ramp and taxiway areas (from spot 7 around west to spot 2, taxiways M, E and F) impact Express operations all that much. Parts of E have been shuttered on and off for construction for the better part of a year, now.
As to the assertion that he is only comparing differences, the fact that Express stays clear of those above areas would tend to change the statistics. I have not been able to use 18L/36R for many months now for operational reasons.
There are other issues, when B3 through B9 simultaneously push, delays occur. Also when CLT, for some reason, put a 330 in B9, I think it is, blocking 7 and 11.
As with Jim, you just put me into the yellow/red on math and have to dig my old books out of the closet. Thank you. Sincerely.