> If he had though about color blind users, normal users wouldn't have issues either.
That's what you meant, right?
Anyway, that's exactly the argument I always bring up: if you design for the colour blind, the deaf, don't assume righthandedness, etc, and you do it well, the interface will end up more user-friendly for everyone.
In your example, adding a hint based on shape/position/lightness (or all three even) as well as a colour is easier to read for everyone. Similarly, using some verion of Cubehelix[0] is the more readable option for heatmap-scales, and again not just for the colourblind but for everyone.
That's what you meant, right?
Anyway, that's exactly the argument I always bring up: if you design for the colour blind, the deaf, don't assume righthandedness, etc, and you do it well, the interface will end up more user-friendly for everyone.
In your example, adding a hint based on shape/position/lightness (or all three even) as well as a colour is easier to read for everyone. Similarly, using some verion of Cubehelix[0] is the more readable option for heatmap-scales, and again not just for the colourblind but for everyone.
[0] http://www.ifweassume.com/2013/05/cubehelix-or-how-i-learned...