I watched Andrew's talk recently, and I highly recommend it to other readers interested in the above topic. It's full of clearly expressed, interesting ideas.

I watched Andrew's talk recently, and I highly recommend it to other readers interested in the above topic. It's full of clearly expressed, interesting ideas. When I read: > What I want is a semi-tangible expression tree that I can manipulate and "snapshot" (to show my work) into Latex. The Latex rendering was easy, but figuring out what "core tree manipulation ux actions" are is another thing. —in the parent comment, it was the first thing that came to mind.