Pleating to the stripe but which stripe

[Nemuragh]

In the USA Kilts videos, their recommendation was to squint your eyes to where the entire tartan becomes blurry. Pick out the strip that stands out the most.
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Trying this suggests the darker blue, wide stripe but it is closely surrounded by light blue lines then yellow and white lines. I wonder if this would be too wide to fit on a pleat or if it would mean some of the adjacent lines disappearing where the pleat narrows (and therefore not being viable).