It is a variant of swathe, itself a word whose Old English origins do not fully explain the way in which it means both a section of mown grass and a wrapping-up in cloth. It could make for a disquisition similar to those in Martin's Picasso play - scandalously overlooked by London, as are the equally witty conceits which animate the work of David Ives.
THE DIVERSIONS prompted by Francis Wheen and Julian Barnes's commentary upon the John Walsh/ Steve Martin "irk" controversy have delayed mention of Martin's casual remark that "in every industry, there's a swaff of people who you would call `well-read' . . . and there's the mass of people who aren't." One boggles that LA should echo to a word last used in 1688.