Well, if any of you are interested in inverse-shading here's the breakdown:
1) Colour layer with flat, original colours.
2) Adjust hue,saturation, and value settings to suit situation (outdoors daytime, indoors daytime, indoors nightime with crappy lamp etc) so it becomes darker, maybe tinted as well. These will be the shadows.
3) Decide on light source and colour background accordingly.
4) Create new opaque layer on top of flat layer and OVER line layer (you know, the layer with line art).
5) Reduce brush opacity and flow (How much depends on the light situation). Colour light areas with dabs of the original colour. The more you dab, the brighter it is, so you get some cool gradient effects if you vary your strokes. Remember to overlap the line art areas slightly, but not completely, to denote light.
I like this method better- It's more fun to do, for one. And it is faster, and that advantage alone would have been enough to make me switch styles.
It's kinda like acrylic in term of technique- you colour the dark areas first, then slowly mix bright colours in.