OK, I'll bite. To test that out, I made 2 images that it should effectively be unable to display. I'm including the originals this time so other people with similar devices can do the same tests.
The first is a 1 pixel spaced stipple pattern.
With this, you technically shouldn't be able to see 8 bands in the middle of the image. Here's the best detail photo I could get of it, looking at it from the left side.
Next, I created 16 shade dither pattern from the palette.
If it's really an 8, it should be able to display this perfectly.
Ooh! Almost! The 3 colors near the middle seem to blend together. That's not good.
Oh well, I guess it's a 4 after all, since it'd be pretty absurd to think it's a 6.