Digital BW, The Print

well, I'd be interested in seeing that direct quote... since there is
no such thing as "sharpness information".

Green is the part of the spectrum to which the human eye, and the CCD
sensor, is the most sensitive. Therefore, the range from darkest to
lightest is largest in the numbers extracted from the voltage of the
green sensor.

A sensor is a sensor, and one color is not inherently more "sharp"
than another. Each sensor simply puts out an electrical current
related to how much light is hitting it. There is no "sharpness"
information.

(There are about 50% more green sensors than those filtered for red
and blue, once again to provide more luma information.)

Luma is just brightness. It has nothing to do with sharpness. ALL the
sensors are responding to luma, but each in only one portion of the
spectrum.

AntiAliasing is a "cure" to color issues, and has nothing (much) to do
with luma. The anti-aliasing filter may be physical (which can lend to
softness issues that can be severe, and easily discernable,  or it
calculated, which produces information depending on how well done the
algorythms are, and the layout of the sensors.)

The need for anti-aliasing comes from trying to deal with a
sensor-group which has two different colors meeting in a sharp line
across it. 

Thus, if you shoot camera RAW, and select one channel, (any channel)
you'll get perfectly sharp information,  since a pixel in is a pixel out.

True: the Foveon does not require color anti-aliasing, but that has
nothing to do with single pixel sharpness.

However, all that said, simply take a RAW camera image (say 3024 x
2024, as it comes from the S2 pro) and select split channels in Photoshop.

You'll get three images with different ranges of gray tones, depending
on the range implicit in the color filter. Each image will be some
range of "black and white" and each image will be exactly 3024 x 2024,
and contain just over 6 million pixels... not 1.5 million. 

I have no idea what "real sharpness" is, but, in terms of raw pixels,
and raw data, from a Camera RAW file,  the 6 megapixel image IS twice
as dense as the 3, and thus provides twice the information to deal
with, and has, hence twice the resolution.

Take a camera RAW of 6 megs, and blend the three layers to your liking
for full tonal range, and you'll have a perfectly sharp 6 meg photo.

Take the color information out of a 3.5 meg photo, blend the results,
 and you'll still have  3.5 megs of resolution.

Remember, we're talking B&W here, not color, which is what
anti-aliasing is used for...

And it is impossible for there to be such a thing as an "interpolated'
RAW file: either it is RAW info, or it is interpolated info, but it
cannot be both, by definition. RAW is what the CCD photo sensors put
out: period. (I understand the confusion, the tyranny of words, that
can arise, since the Foveon only puts out a "raw" file, but to keep
the terminology correct, once that file is interpolated, it is no
longer "raw" in the sense normally used when speaking of digital
camera RAW files.

Yes, the Foveon is great, particularly for color. Excellent stuff. But
there is a trade-off on sheer resolution vs the lack of need for
anti-aliasing. Bottom line, for color, is how you like the result.
It's the photo, stupid!  :-)

 But for B&W, if using RAW files, then there is no anti-aliasing, and
no matter how you slice the pie, 3.5 megs is less information than 6.1.