Didn't get much different from the first go around but here's my take...
Ok, I'm going to proceed carefully and choose my words here, but only because the concept I'm about to explore requires a shift in the way you think about colour. Because you talk and think in absolute terms and I'd like to show you the relative nature of colour.
First I'll show you your edit in absolute terms and discuss the difference in absolute terms. Then I'll show you the image in
relative terms and hopefully demonstrate the relative nature of colour. I'm going to show you both edits twice, I'm going to present both images exactly as they are making absolutely no changes at all. Now if colour is absolute then you will always see it as constant and therefore the individual edits will look the same because they are the same. Now if colour is relative you'll see a difference, and I think you're going to be surprised at the difference when I show you your edit the second time.
Here they are in absolute terms, both edits together. Fullscreen your browser so you can see them at 100%:
The first thing we notice is that we both do selective editing. If I concentrate on the headstock you'll see your edit has far more vibrant (saturated) colour. I'm not sure if this is deliberate or the result of not separating your colour from luminosity. When you use an adjustment layer such as curves or levels in Photoshop with the blending set to 'normal' you adjust both the contrast in luminosity and colour. Increasing the colour contrast changes the colour by way of saturation. You can separate this by changing the blending to 'luminosity' or 'colour'. Luminosity only changes the bright/dark and keeps colour constant, colour only changes the colour and keeps luminosity constant. If we look at the music you see I've retained more colour here. Here's an enlarged comparison of the headstocks with your edit on the right:
You have indeed created a far more neutral tone in the guitar and it's here that you talk in absolute terms. You think in terms of the guitar being too blue so you select that item and directly adjust that property. But perhaps this is not the case, perhaps it's not the guitar being too blue but the rest of the image being green/red? This is not as odd as it sounds, and if we look at a direct comparison of the two fretboards side by side (your edit on the right again) without making comment yet...
Now I think we can agree that both full edits show a depth and richness of colour though in different areas, or do they? Now let's look at them again and this is where I hope you'll see the difference. Go back to mine and your original edits and 'right click open in separate tab' for both of them. The idea is that we now look at both images in isolation, separately but in sequence. Look at mine first for about 30 seconds then flick to yours.
Oh dear, what happened to the colour?
Colour is in fact constant, it just that we see in relative values and the eye adjusts the balance. Cyan appears slightly more blue when placed next to green and slightly more green when placed next to red. It is the variety of colour in context (i.e. of roughly equal saturations) that not only stabilises the viewer's perception but also provides the contrast or difference that brings the colours forward. It's what I mean when I (broadly speaking) say that modern editing tools, and the way we use them, are subtractive. When you increased saturation you brought the dominant hues forward
by subtracting the other colours, when you removed the colour of the guitar you did just that,
subtracted colour and equalised the values across the image.
Let's look at the fretboard again. Look at the variety and contrast in colour on both sides. Does the left really show a blue cyan cast or does the right show a green one? Going back to my earlier statement:
You think in terms of the guitar being too blue so you select that item and directly adjust that property. But perhaps this is not the case, perhaps it's not the guitar being too blue but the rest of the image being green/red?
Not as odd as it sounded at first. Have you really given the fretboard a more neutral tone or have you just removed the contrast in colour that made it appear too blue/cyan? When you viewed the images side by side you saw the colours of both in reference to the colours of both, when viewed separately you see the colour of each in reference to the colours they contain. Although colour is constant, the way it appears to the eye is very much relative.
This has turned a fairly ordinary image into a discussion on one of my favourite subjects, please accept that i didn't start the thread with this intention but I hope, as always, that it might be thought provoking and useful.