Doesn't work as well when you just want to pop out a quick small prototype so you can test it, iterate, and do it again, but definitely that works for some appl

Doesn't work as well when you just want to pop out a quick small prototype so you can test it, iterate, and do it again, but definitely that works for some applications. And as they mention, path optimization can also help here. As a contrived example, if you're building an upside down extruded "T" shape, maybe you could work on building up the stem as high as possible as quickly as possible, and spending the "cooldown" time working on extending and building up the base. I'm not aware of any 3D printers that move beyond the simple "build from the bottom up" approach[1], but it seems possible to take into account the bulk/size/shape of the printhead and do some advanced things -- if the payoff is there. [1] I also know approximately nothing about this space, I'm not speaking from an area of expertise, just novice theory. Maybe this is already being done or maybe it's simply impossible because the printhead is just far too bulky.