[henryrp]

Another aspect of all old performance materials is the utter absence of rehearsal letters ("A", "B", "C" etc.), measure numbers, little eye-glasses ("watch the first chair here"), bowings, fingerings and all the other things contemporary classical musicians need to put into their parts during rehearsal. It really makes you wonder what a rehearsal in the 18th century could possibly have been like.

And yes, I'm pretty sure Bach saved as much paper as he could. The autograph score to the Christmas Oratorio uses spare staves all over the place. This is not a page-turning consideration. An aria may coexist side-by-side with a chorus for many pages at a time to evidently prevent those 2-3 staves at the bottom of the page from being wasted.