Here’s an internal #Commodore document written by Chris Green on speeding up the blitter. This document was generously contributed by Randell Jesup and is being shared with his explicit permission.
Potentially rather interesting! But the document is undated, and the ‘commodore international history society’ conducts its business in a closed Facebook group, so it’s all a bit opaque.
A key phrase to search for in case this text appears on the web: “proposed new register is BLTA2LWM”
Here’s the front page image as posted on twitter(!)