I played in the pit for a local production of this show in ’95 or ’96. I didn’t want to do it after listening to the original cast recording because (I thought) it sounded creepy and I didn’t like the steam whistle. It turned out to be one of my favorite shows and great fun. Ironically, the harp was real and the steam whistle was electronic!
As to shrinking the pit orchestras, there’s a group in New York that puts on shows called Forbidden Broadway. The songs use melodies from popular shows with lyrics that are parodies and funny critiques/comments on the shows and/or performers. Their performances are available on CD.
One that really caught my ear was the opening melody from Sweeney Todd (“Attend the Tale of Sweeney Todd”). The words tell of a production that was so scaled down that they called it “Teeny Todd.” At the end, the lyrics say:
“To think that one of his (Sondheim) shows today
No one can afford the original way…
It’s teeny Todd…
The smaller version of Sweeney.”
It all comes down to costs. It’s sad.