It's very useful for sure, especially when you want to look through the old stuff, I started signing it in 2006, wish it was earlier
Last year I made a few documents with various purpose, like a document for random sketches, a document for Hexameron sketches, for old-art-redraws sketches, etc. It's a bit messier than having a document for every sketch, but saves space If I make a sketch from a particular comic in Random, I relocate it to it's proper place, and if I am going colors, I make a separate document ^^