Here is some good, current information for you.

The reason for DPU is for fuel savings, not power. It has been determined that average fuel savings is around 6%.

The Graham Line requires 424 TPA, the Blues require 172. In no way does the graham line effect the amount of power on the stack trains.

There is no such train as a KG1TA. No intermodal trains do regularly scheduled work at Albina with the exception of the KTMBR (sets out cars on the way to Brooklyn) and the ZKCBR (occasionally sets out beer loads).

The occasional mid-train DPU on the KPDG2 is almost entirely due to the logistics of building the train with loads coming from Tacoma, Barnes and Brooklyn at different times while still attempting to maintain a scheduled Albina departure.