post processing - Does Lightroom apply edits in the order I do them, or does it intelligently reorder them?

The matter of the correct order of applying sharpening has been discussed various times (I will pick this question as an example, but it's not the only one), with a clear consensus which can be summed like: "apply it as the last step" which makes sense, since you are trying to make up for details which are not "really" present in the raw image (due to AA filter, for instance, or to inherent features of the camera sensors). Furthermore, Lightroom is defined as a linear editor: if you want to "non linearly" remove a previous step you have to resort to a layer-supporting software, like the Gimp, Photoshop, or what else you favor.

But then, the interview to Tim Grey featured on our blog contains the following sentence (after saying that he agrees with sharpening as the final step):

But overall, you don’t have to worry about the timing of sharpening in the context of a Lightroom workflow, in large part because all of the “real” optimization work on your images doesn’t actually apply until you export the photo in some way, and Lightroom is intelligent about that process. Sharpening can be applied in the Develop module at any time, and then use the output sharpening options when preparing an image for final output.

What exactly is this "intelligence"? I imagine that if I were to over sharpen in the first stages, then reduce noise and sharpen again (duly reducing the image quality, but assume for the sake of it that I'm aiming for that) LR should not be able to "condense" the sharpening steps and apply them as a final step, since that would "void" the (admittedly silly) point of my edits.

I tried to interpret this as something like "if LR is able to prove that you are not playing silly tricks with sharpening (for instance you only have a single batch of sharpening edits and a single batch of noise reduction edits?) it will intelligently reorder them and apply as a final step.

Then I thought about the (not well named IMHO) import setting called "None", which is the default and the one that I had been using for a while before picking "Zeroed" which, as far as I can't tell, really doesn't apply anything. This "None" setting applies by default a moderate amount of sharpening (in LR 4 it is amount 25, radius 1.0, detail 25, masking 0), together with color noise correction (25).

So it seems that in its default setting LR is applying sharpening as a FIRST step, which would not be a smart move on the part of the smart LR engineers if it was such a killer for Image quality.

So my question is fourfold:

• (once again) is the order of sharpening IN LIGHTROOM (as of version 4 if it matters) really important and in which situations?


• is the use of the Zeroed setting a good idea to avoid a "first step sharpening"?


• is the choice of the "None" setting with its default sharpening an issue, a non-issue, or what?


• is LR really a linear editor or it has the habit of reshuffling (without notice) the order of the edits and I misunderstood the meaning of "linear"?