Thats a good write-up. Thanks for posting the link.
I always thought they took them over Cajon to save from keeping helpers entrained over Vincent Hill and the grade up out of Newhall to Slymar... back then it was a recent change from TT-TO to DTC on the Saugus line.
We used to pace them up San Fernando road in the late evenings, and bag shots of the easbounds billowing smoke out tunnel 5 on Tehach...
Good times! ...those were the days.
Jeff