BTW, this is my personal usecase scenario where editing a gradient in GIMP was 
unexpectedly a painful thing:

I was trying to create a sepia-like gradient -- a gradient that fades from 
black to sepia (for simplicity, let's just say RGB #804000) to white.  Y'know, 
something I can just Gradient Map onto a grayscale image later on.

This poses several challenges:

1 - Because the endpoints are black and white, any blend between those 
endpoints will only ever produce a greyscale gradient.  This applies in both 
RGB and HSV space (black and white by definition have saturation=0).  Therefore 
I require a node in the middle to specify the desired color.

2 - Because I will be tweaking or changing the color to suit my tastes (there's 
a specific image I'm trying to match), and this gradient is contiguous, I 
constantly have to tell GIMP to "Load endpoint's color from > neighboring 
endpoint" every time I make the slightest tweak to the node's color.  This 
doubles the number of steps I have to perform just to set one color -- but as a 
small optimization, I can simply tell GIMP to use my foreground color in the 
meantime.  The only problem with doing that, though, is once I'm finished 
tweaking the color I have to set the color type (and remember, on both sides) 
back to "fixed" before I save the gradient and quit GIMP.

3 - My chosen RGB tone doesn't exactly carry the same luminance as a 50% grey, 
does it?  So I need to apply the equivalent of a midtones/gamma adjustment to 
it.  I set each segment to Curved blending, drag this node to the left, 
brightening the overall appearance of the gradient....

4 - But I see another problem - the midpoints between nodes (white handles) 
don't move in  proportion to the overall length of their segment.  So I have to 
adjust them too.  Now instead of just manually positioning one handle, I now 
have to manually position three.

5 - And because this gradient should approximate a curved blend, I can't just 
re-center the handles in their respective segment - if my middle node is 40% 
from the left, each segment's midpoint also has to be 40% from their left 
endpoint too.

6 - And did I mention that I'm alternating between tweaking both the color and 
position as I go along?

7 - Cue banging of head against the keyboard in frustration and having to undo 
whatever steps GIMP may have interpreted those keystrokes as.  (Oh, wait, the 
Gradient Editor doesn't even have its own undo system -- cue banging of head 
against monitor....)

Now in some alternate universe where editing gradients is done solely on a 
conceptual level, I could have just:

a - Specified the starting color (RGB black) in HSL values of:  hue = 30°, 
saturation = 100%, luminosity = 0%.
b - Specified the ending color (RGB white) in HSL values of:  hue = 30°, 
saturation = 100%, luminosity = 100%.
c - Assigned HSL color mode to the segment.  (midpoint of segment becomes:  hue 
30°, saturation = 100%, luminosity = 50%, a.k.a. RGB #804000)
d - Specified Curved blending on the segment and adjust the midpoint until I 
get the desired result.
e - Done!

Yeah, that would be nice....

-- Stratadrake
[email protected]
--------------------
Numbers may not lie, but neither do they tell the whole truth.
                                          
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