Oddly red+green light produced yellow. At least it seems odd to me, but I can't get into others' heads. Yellow looks completely different from red and green to me, whereas red+blue produces magenta which looks like a mixture of red and blue. Blue+green produces cyan, which is more like a light blue to me, but maybe if it is darker it would look teal, which is blue-green.
It's odd that colour circle (wheel) diagrams look right, and violet looks like an intermediate between red and blue. Is this a perceptual matter, or is it that extreme red is twice the wavelength of extreme blue, in which case it's physical? If so, why should this be the case as our eyes are just adapted to the range of light mostly produced by our Sun?