The reason why B-32's are commonly relegated to yard service these days is simple. While they were originally delivered as road power, they were never really meant to be much more than a stopgap measure, until more modern units (the P40s and P42s) could be acquired. (It helped, at the time, that Amtrak got a sweetheart financing deal with GE for the B32s.) As the old, inherited yard power began to approach or exceed its useful life, B32's were an easy substitute, since they were available, on account of having an adequate supply of modern road power on hand by that point.
Trust me, no yard crew PREFERS a B32 over a purpose-built switcher. But all too often, that's all that's available.
I sort of wish the modern-ish MP15's were available system-wide, and in larger numbers, but they seem to be confined to the east coast.
(Side note - B32 actually aren't bad in road service, assuming multiple units on the train. Aside from a few limitations, they can dig in and pull almost as well as their more modern counterparts. However, single unit service is awful, because running HEP just seems to suck all of the life out of them...)
hey there guy