Tints = added white (brightness) to a color hue.
Shades = added black (darkness) to a color hue.
Tones = added gray (contrast) to a color hue.
Having been recently studying color theory, I would say the short answer to your question is: yes. Tints/shades are technically adjustments to the "value" of the color, which is to say how much white or black is added to the color to get darkness, with the same hue and saturation. The hue is the starting color from the spectrum of visible colors, while saturation is how much of the color is present in the color. You should be able to freely manipulate the value without affecting the 'harmony'. Of course, as a programmer who has worked with different aspects of graphics and dabbled with the creative, artistic side of things as well, I think a lot of the problem is that these laws of harmony are all really products arising from color interactions. These interactions occur in psychological and cultural perceptive constraints - in addition to physical limitations of vision and the nature of light waves. So everything is pretty mutable and arising from lots of conflict. Do you use the rgb/cmyk color wheel or the traditional ryb? Additive color mixing or subtractive? Nothing is really set in stone...
Having been recently studying color theory, I would say the short answer to your question is: yes. Tints/shades are technically adjustments to the "value" of the color, which is to say how much white or black is added to the color to get darkness, with the same hue and saturation.
I haven't studied the theory of colors but using my degree in Physics, Mathematics and Computing I always thought that there are just three primary colors out which all other colors are made. These are Red, Green and Blue. To get darker colors you simply add little bit more of Green and Blue and so on. In fact if you use pure pigments of Red, Green and Blue and mix them in equal proportions you get white! Now this must be magic or some African witchcraft!
Yeah, I have some physics behind me and a lot of math that I keep forgetting.. Color involves all of that, but also more. Look at this guy's stuff for some concise scientific background: http://www.poynton.com/notes/colour_and_gamma/ColorFAQ.html
You are right, rgb can be used to fully describe any color. As can any 3 dimensional space that can be mapped to the CIE XYZ coordinate system. HSV is probably best for thinking about it for us. Rgb works, but was developed because of the limitations of the human eye's cones and rods, and that's how we started with computer graphics. However, these are working with light as the medium and so do additive mixing of colors. Artists developed all their stuff from mixing paints, where the mixing of two colors that each reflect a part of the spectrum combine to form a substance that reflects *less* of the spectrum and so subtracts. Thus the so-called subtractive mixing, and why the ryb color wheel is different than the rgb/cmyk. And note: I think the great artists are definitely a source I consider valid for any idea of color 'harmony', right?
I've just started checking out Kuler, and have looked at a lot of color wheels. Kuler mixes with light, but seems to mimic the subtractive blending in their calculations. Try the base color red: ff0000, then select the complementary scheme. The wheel shows 180 degrees on the wheel at full saturation to be 00ff48. With rgb, it would be 00ff00. I think Kuler is closer to the artists' color wheel than rgb, but still not fully on. But I'm not sure..
**Any color gurus from Adobe want to weigh in?**
While you're at it, I've been coding some color blending tools to help with my website, and I would love to get the algorithm behind the Kuler wheel and rules, if it wouldn't step on any toes. I looked at the apis and the developer forum, but haven't found anything.
I love reading this thread! I'm just a nut, not a math/physix pro. I became less bound up with color models when I read (1992 or so) an article about creating a palette from mixing all three primary colors. The color wheel (as far as I could tell) never does this. It made for a nice mellowing effect. In those days I just had this palette I'd taken from pantone colors (nowadays I'm really mixed up by pantone and all it's variation palettes -- especially as I bounce from on-screen work back to print and then try to please both with same graphics) and when I was ready to print something important I'd have the printer print my palette, chose my colors from the print, and then hope the Print Job would turn out right. I love Kuler and have whiled away some time there, but another big Click for me was from a book in an art store that showed creating color harmony by taking two colors (whatever, not necessarily opposites or triads etc.) and using the blend tool in Illustrator letting the software graduate a few steps between the two, choosing one of those blends to use. I use that method a lot. And I go to the paint store and get color chips. That's not a great technique, but I do that. And I ponder Leonardo, grinding the lapis lazuli and who knows what else, taking the yolk ... making modern day restorers grimace at the stucco conundrum. The color models are so -- rigid!