I think this advice is relevant HP48 or not (as I read it)… though perhaps the meaning of “heavy calculations” is doing all the work then… since on modern hardware you can just crank up the cycles per frame making “heavy calculations” unimportant, where as I imagine on the HP48 you’re much more limited to what you have.
OR perhaps the HP48 is writing to the screen real-time, instead of buffering? That would make a huge difference also… do you know?
The modern stuff (Octo) is all buffered so you can do anything you like so long as the screen is “ready” before the next 60Hz tick.