Jay,
I don't think anyone said anything about dieselizing the line, just that it was nice to have diesel backup and to push locomotives around in the winter time.
I would have to agree that starting a diesel and charging up the air is a lot less time cosumer and practical than firing up a K-36 to shove a locomotive around the yard or to take a small work train out prior to the season starting.
Plus they'd have to go through all the "Goats" to run regular Diesel Passenger trains.
Your post said that 3 are under steam (463, 487,489) one more soon (497) one in the Fall (484) and two over the winter? (488 and what?)
Do you have news or a timetable for 483 or 492?
Kevin