They are trying to say they don't need to wait between layers. They display layers without pauses so it is a continues movement of the build plate. For top down: Currently we normally dip down to cover the build plate with resin then move back up again, wait for the resin to stand still then display a layer. Bottom up: Display the layer, move up a bit, dip down again, wait for a bit then display the layer again. They say they are able to move the Z without ever stopping. Helps that the features are 1mm thick. I am going to try the same as what they did, but with 4L of resin in my vat I think it might work better with my micro vat that will have 0.7L of resin. We will see.