@mergen3107: -b just draws with no refresh, that's the whole point (hence the final -s call in the example above)
. Because as you've noticed, if you start mixing colors other than B&W in a bar with incremental refreshes in quick succession, things start to look wonky.
Note that the EPDC itself will probably inhibit refreshes if the content hasn't been changed, given the waveform mode being used (because AUTO will probably default to DU given the type of content being drawn).
(e.g., if you repeat
fbink -Mm 'Wheee' -W DU, the subsequent calls won't actually refresh the screen, because there's nothing new to show).