I didn't use Kodachrome 200, but I have seen a lot of it over the years through the display of slides shot on the stuff by my father.
Kodachrome 200 does produce a pretty good level of apparent sharpness when projected through low/medium quality projector lenses. That impression, in my opinoin, is diminished when the slide is projected via a lens of very high quality.
Is it possible that this was one of the design goals? Given that it was a high speed slide film for the times - was it optimized to give high relative apparent sharpness on "mainstream" lens systems?
Perhaps Photo Engineer knows...