It would appear, that my experience may not be uncommon, as shown in the writing of José M. Parramón, a strong proponent of Thomas Young‘s Colour Synthesis as modified by Hermann von Helmholtz, who wrote in the prologue of his book  (footnote 11.)  on the subject of Colour Theory:

        " When I began to study colour, I found to my surprise and astonishment, that most, if not all, books published on colour theory still talked about the spectrum of seven colours that still included indigo. They failed to take into account that colour photography and television had demonstrated, physically and chemically, by means of the additive and subtractive synthesis of colours, that there existed only three primary colours and three secondary colours, six in all. It is, therefore, impossible in theory or in practice to have a seventh colour. I also discovered that many writers still think of orange as one of the primary pigment colours. However, it has already been demonstrated, not only by photography and television, but also by photo-mechanics and graphic Arts, that subtractive synthesis does not consist of the mixture of yellow blue and orange, but of the mixture of yellow, blue and crimson. Crimson is a light red colour scientifically and technically known as magenta, unnamed, was adopted by photographers and graphic artists when they print in full colour, with just three colours and black. "