The color names on the chart are sort of useful, in that the sequencing is valid (though often ignored by both tobacco wholesalers and cigar vendors alike). The colors shown, however, are cartoon tints of the same cartoon leaf. So they are not really useful in judging actual tobacco color, other than, again, the general sequence. The statements about sourcing and methods are nonsense.
So, to learn the formal names of progressively darker wrapper leaf, the chart may be helpful.
Bob