Matt's done a great job getting Stewart's Old & Rare on-line along with several other important early works. They provide an invaluable research resource but their contents are often suspect and they should always been view in the context of when they were produced.
For years Stewart's work has been hailed as a sort of Holy Grail with, by his own claim, the silk plates being carefully matched in both sett and colour to the originals. Over some 25 years of research I've been fortunate to examine a number of the original artefacts that he claimed to have reproduced accurately and I’m forced to the conclusion that he was either colour blind or full of his own self importance. There can be no other reason for such huge discrepancies between the original pieces and his 'accurate' copies.

I've written elsewhere about finding the original Culloden Coat and just how different the original and Stewart's rendering of the tartan are. The same can be said for his; Plaid found at Culloden, MacDonald of Kingsburgh and a number of the other older tartans he includes.

Does all this matter? Well yes is does, especially where he gives completely different colours or settings and claims them to be correct. At best this was sloppy research but in doing so he created a truism that has been perpetuated, not least by his son in The Setts, and which continues to be passed off on the unsuspecting.