Trying it again as an experiment -- I used to do a lot when I was a teenager. And there are discoveries.
Such as: when I was a teenager, I would have pages with asterisks all over the place pointing out the stuff in the margins that went there, but I had not dreamed up until half way down the page from there. It is not so pronounced now, but while there are pages with no such asterisk, there are pages with three or even four passages to be interloped.
Interloping scenes is much harder while handwriting.
Figuring out what you called that silly location that you didn't bother to take notes on is a lot harder in longhand than in electronic, even if your story is hundreds of pages long, and you're not sure what to search on.
And I still slack off on the sensory impressions in the first draft. I noticed this not so much for the sensory interpolations I added while writing but when typing up a story and having to add detail after detail trying to make it more vivid.
Think I'm going on with some longhand experiments. Since what really counts is the final product.