The gradient editor in Gimp has a lot of limitations in comparison to Photoshop.
There is no live editing.
You can do live editing in Inkscape but switching between the two programs for a text effect is not ideal.
In Inkscape you can give each object (like text for example) a fill and a stroke.
A fill can be colour, a gradient or a pattern. Same for the stroke. They dont have to be identical and thats the cool thing:
you can give your text a fill of, say gray, and make the stroke a gradient.
This is especially useful when you want to give your texteffect a stroke that looks shiny. And the best thing: you can edit the gradient and see how it immediately changes the look - in realtime so to speak.
Like adding colourstops, position them wherever you want and change the angle of the gradient.
Thats the power of vectorgraphics. Doing the same thing in Gimp with the gradient editor would be very hard and tedious.
As an example, here is a texteffect i made in Inkscape:
and here is a screenshot, so you can see the gradients:
(The diagonal line with all the little squares, thats the gradient of the stroke and each square is a stop for a colour. You can move these stops around and change the colour whenever you want)
In this tutorial i show you an easy way of getting a shiny stroke on a metallic looking text.
01. I used a canvas of 800x300px and the font Ethnocentric 194px.
02. Create a new transparent layer and name it 'Gradient'.
03. Alpha select your text and save it to a channel.
Deselect, turn on the visibility of the channel and set the fill opacity to a 100%. Now everything outside the textboundaries is black.
I made this gradient, and you can download it from mediafire if you want.
04. With the gradient layer active, stroke the gradient from the top to the bottom of the text !
Make sure 'Adaptive Supersampling' is ticked and hold down CTRL to get a perfectly straight gradient.
05. When you are happy with the look, turn off the channel and apply a layermask 'From Channel' to the gradientlayer.
Also get rid of the basetext layer, by either turning it off or putting it under the Backgroundlayer.
06. For the Stroke we duplicate our gradient layer and rename the original into 'Stroke'.
07. Alpha select the basetext and grow the selection by 4px (or whatever you like for the stroke size).
05. With the layermask of the Strokelayer active, fill the selection with white.
06. Deselect and desaturate the Stroke layer.
(For our chrome-trick to succeed, we need the layer to be grayscale - otherwise the blue will become brown.)
07. When you now play around with a Value Curve, you get your shiny stroke.
Shaping the curve gives you a bit of control how the light and dark areas will distribute so that you get a shiny look in the end.
08. For the finishing touches i added a Dropshadow (Blur 10) and tweaked the original Gradient a bit with a Value-Curve.