In the previous post I mentioned that shorthand is optimized for writing instead of reading. I hadn't considered the possibility of a write-optimized form of English until I read this article by a journalist who uses a high-tech pen to take Gregg shorthand during interviews. It piqued my curiosity, and I started playing with shorthand. That was almost ten years ago. I'm not a journalist, and I don't have a high-tech pen, but while I rarely need to take notes at anything near speaking speed, as someone who writes a lot I have appreciated being able to write shorthand, and for a variety of reasons.
The primary reason is that writing shorthand interrupts my reflex to edit. It's tempting to write sentence by beautiful sentence long before a complete thought is present, and once the full thought is present, those beautiful sentences usually need to be rearranged, clarified, and made beautiful all over again. I've found there's less rework if I postpone structuring and polishing until all the material is down on the page, even if that material is ugly. Writing in shorthand helps with that. Since it's more difficult to read, I'm not as easily distracted by what I've written and I'm less likely to revise it.
Not only does shorthand inhibit going back to edit, the speed of writing it helps maintain forward momentum. It's possible to write much closer to the speed of thought. As with all first drafts, those thoughts aren't well expressed, but keeping up momentum allows exploring and developing the branches of an idea, and it grants a much fuller picture of a overall concept that can later be trimmed and refined.
One other reason I've enjoyed shorthand is that I get to pull the pen as I write. Being left-handed, I usually push a writing utensil across the page, and while I did learn in elementary school to angle what I was writing on to avoid curling my hand into a hook, I still felt like traditional longform wasn't as comfortable or fluid as it seemed to be for right-handers. So when I started learning shorthand, I decided I'd flip it and write from right to left. Naturally that has some challenges, such as having to mentally mirror images in any references, but since no one but me needs to read my shorthand, it hasn't been much of a problem, and I've finally been able to enjoy the comfort and fluency that I imagine writing cursive is for practiced right-handers.