Yeah, I like it. I used this as a tutor in more finicky exercises when it becomes really important to keep 2-3 very similar, but different things apart. It takes a bit of dexterity, but you can switch fluently between 3 different whiteboard markers held in one hand while writing, haha.

I am kind of wondering if a semantic highlighting makes sense as well. You often end up with some implicit assignment of lowercase latin, uppercase latin, lowercase greek letters and such for certain meanings. Kinematic - xyzt for position in time, T_i(I_i) for the quaternion or transformation representing a certain joint of a robot.

It's easy on the eyes and it can make reading lots of equations less awkward if done correctly. I remember finding out this was possible while I was working on an assignment in Latex - it looked amazing.

It takes a little bit of work to colour in equations but I hope more people start doing it (including me, I'd forgotten about it for a while)

Pedant-man on the scene: this is just highlighting since the highlighting isn't derived from syntax.

It's been around for a long time (centuries?). In most textbooks, you'll get different semantics for italic and bold faces. Modern textbooks with color printing often use color in semantic ways.