I would not say it was pointless, I think members are aware that the colours are but a guide. There are even different types of "white", and when we used to set the grey-scale on CRT colour tvs a fluorescent tube was used as a reference for the adjustments, I think it was called 'Northern Grey Sky' shade of white. However, I do think that the depictions given will (at least) help to distinguish between light,medium and dark red.