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While it would probably get pretty decent results, I don't 100% agree with that approach.
Master darks will get rid of most hot pixels without relying on dithering and outlier rejection. Dither and outlier rejection works pretty well too, but if you have pixels with offsets or with more dark current than others, they will get rejected as outliers where using a good master dark might salvage them. Will the difference be visible? Don't know!
Bias frames are the quickest and easiest of the calibration frame types to shoot. It is easy to generate a good master bias for whatever gain and offset settings you are going to use.
If you calibrate your flats with dark-flats, that is fine and will work well, but your flats need to be a matching exposure time. Cameras that produce good bias frames (Which the 2600 does) allow you to shoot flats of varying exposure times and calibrate them with a master bias to get rid of read noise.
I tried an experiment just now. I created two master flats from a recent nights flat frames, one with the master bias and one without, then I loaded both as light frames, and as darks (So they straight subtracted one from the other) When each one was calibrated by the same one, black screen, when calibrated by the other, the attached grey crosshatch is the result.
Then I unloaded them as darks and loaded them as flats, the most visible one was the flat created without bias calibrated by the flat created with bias. The other way round produces a negative image of this and it does not stand out as much.
As always though, if you shoot flats and are happy with the results without calibrating them with dark-flats or bias, feel free to ignore me and continue! With my old 294, you really HAD to use master darks and HAD to calibrate flats with dark-flats or the results really suffered, the 2600 (Both MM and MC) is not nearly as fussy, there are some images I shot with my refractor and 2600MC that I didn't bother using flats for, I just cropped in a little to where the vignetting was not visible.
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