In all cases, it is changing the video from what was intended. The effect may or may not be liked by you, but it is not giving you more real detail than is in the signal simply upconverted. It is analogous to (but obviously not identical to) turning up the sharpness control on your TV. You may or may not like it, but either way, it is changing the image from what was originally intended.
That's all fine and well, but for Television and DVD's which don't have the resolution of BD's, the Darbee processing may provide a visible improvement on the picture, getting you something that appears to have have better resolution or a sharper image. Not liking the processing because you don't like how it looks is one thing. Dismissing it simply because it's not the original signal is something else entirely.
You seem to be forgetting my earlier post (
with emphasis added):
Whether one likes it or dislikes it, the Darbee processing is giving one something different from what is on the disc, and is different from what the filmmakers intended. From looking at samples online (and varying the effect), I am not a fan of it, but if others like it, it is fine with me if they buy it.
If people like the effect, and wish to pay an extra $100 for it, then they should do so. I do not like the effect, and so I am not willing to pay the extra $100.
The comment about it altering the video from what was intended is there to keep things in perspective. If accuracy is desired, then the Darbee processing should be off. (This is true regardless of the source; but, if you like to alter some sources but not others, that is fine; you should feel free to do so.) Accuracy is not what everyone wants, in video or in audio, and they are free to alter the signal in any way they please, as long as their equipment is capable of it. This is analogous to someone artificially boosting the bass or otherwise changing the sound from what was recorded. One may like it that way or not, and one should do what one wants regarding such things (as long as one is not bothering others, like the neighbors with excessive bass). But one should also not be deluded about what it is that one is doing. It is fine to alter things from what is recorded, but one should know that that is what one is doing.
Darbee makes the picture less accurate. One may like it that way, and if one does, then one should feel free to use it. And if someone wants to turn up the color control beyond what is the standard, one should feel free to do that, or the contrast, or any other control one has. But, again, in such cases, one should not pretend that deviating from a properly calibrated image is more accurate, and one should realize what it is that one is doing. That in no way is a suggestion that people not do it, if that is what they really want.