Because you want an internal infrastructure that allows you to replace the scanner easily. Those thing brake down, or more importantly gets replaced with faster new scanners.

One of my clients has a scanner farm that scans documents, then the images are sent to a OCR server farm. It's way easier to replace any part if it that way (we're actually trying out a new OCR suite right now so I'll test this one).

Even if you just have one scanner and does OCR on the same machine, braking it up this way makes it easier for you in the future.

Not really. Unless there was an actual advantage to having the gene there will really not be a "sufficiently small effect" as long as it's greater than zero.

And there IS an advantage of having this gene: Scaring.

Scaring is faster and fixes you up good enough for most part. Regenerating takes so long you might very well die from the damage before it's finished.

It's not equivalent. In a CRT the "image" only appears when the ray passes a certain pixel, the pixel then goes more or less black. In a LCD the pixels are shining all the time, and then suddenly changes color.

The effect of this is that the brain interpolates better on a CRT, when the pixel is black the brain fills the void. This does not happen as well on LCD, which is why we need much higher refresh rates on LCD's to get the same impression.