Oh, I see what you're saying. But if the game is running at 60fps, this means that Stella should be able to pull off 1/60 second controller delay, right? Instead, it feels more like 100ms. And again, with the framerate boosted to 120fps, the lag disappears, so it's not a driver issue.
Also — on the Atari, the drawing is scanline by scanline, right? So won't the paddle area still get redrawn only once every 1/60 seconds?