Does anyone know for sure?
Faster to hand copy? I thought all what they did was roll some ink on the plate and the roll the paper through a machine that pressed the plate into the paper to make the music -- a printing press. People wouldn't be that fast or clean.
You said the 19th century, the 1800's. The mechanical revolution, steam engines, and all that.
Beethoven was even going to publishers to have his music printed, wasn't he? And wasn't he a stickler about details before sending his copy to the printer?
The only people I've ever heard of trying mass produce things by hand were monks, but that's well before the 19th century. More like 1200's roughly, right?