Your mention of having power on each end intrigues me. I live in the vicinity of Tacoma and after seeing Steve Carter's photo of the Roy Turn recently I got to wondering how the several customers on the south end of what's left of the old Tenino line (which goes through McChord AFB) get served by BNSF. In the photo both units were on the head end, but in looking at current Google aerial views of the line down to Roy, it would definitely appear that an engine on each end would be the easiest way to work those industries south of the air base. That's assuming that BNSF's Roy Local cannot use the Sound Transit tracks south of Tacoma and must go all the way around Point Defiance to gain access to the Prarie Line. Then they have to reverse direction to go from Lakewood south to Roy. After returning to the old Prarie Line they must reverse to get down to Nisqually and the double track main.

So...the photo notwithstanding, does the Roy Turn typically use a locomotive on each end while getting to those remote customers?