Below is an extract from an article by an expert on highland dress. He was writing about the plaid...
"Just a few quick notes on how this large wrap became the kilt of today. One story commonly repeated is that an Englishman named Thomas Rawlinson opened an iron-smelting factory in the Highlands around the year 1730. His workers all dressed in the belted plaids, which proved too hot and cumbersome for close work in his factory. He solved the problem by cutting the garment in half. The lower part could now be worn separately and the upper part discarded when coming indoors. This is considered proof that an Englishman invented the Scottish national dress.
The problem with this story is that we know of numerous illustrations of Highlanders wearing only the bottom part of the belted plaid that date LONG BEFORE Rawlinson ever set foot in Scotland. Remember that the belted plaid consisted of two widths of material stitched together. If one neglects to stitch the two together, and only the bottom 4 yards are worn, pleated and belted around the waist, the resulting garment is called the feilidh-beag (little wrap). The word is often spelled in English phillabeg."
(Roget's Thesaurus lists kilt and filibeg - another spelling - as synonyms.)
I wonder if the above is the discredited story of an English kilt-inventor you referred to, Steve.