"...you don't notice the blackout..." Maybe you don't, but I did. The screen flashed and you'd see the squares on-screen for that split second. I certainly was

"...you don't notice the blackout..." Maybe you don't, but I did. The screen flashed and you'd see the squares on-screen for that split second. I certainly wasn't fast enough to see the sequence of the squares, but I'd see them appear. I'd be interested in more technical depth on this exact hardware. Specifically, was each square on-screen for a whole frame or did they draw one square per interleaved field?