The term tank is defined by X-Marks, not me, or Grant. Since the term is listed in the FAQ's, then we should stick to it.

Saying that a Matt Newsome Box pleated kilt is not a tank doesn't lesson the respect and pride that we hold for the garment. As in the the FAQ's, Quote A 'TANK' is defined as an eight-yard, wool, hand-sewn, traditional kilt. ie., "It's built like a tank." (coined by Jimmy Carbomb c.2005) Unquote

Matt's handywork qualifies in all but the eight-yard area.