twin groove furling foils

[osteoderm]

Flipping through a copy of the West Marine master Cataloge ('05), i noticed a bit in an "info box" citing one advantage of twin-grroove furling fouils being that you can use them to fly twin headsails (poled out wing-on-wing) for downwind work.
Years back, first encountering twin groooves, and not (then) being a racer savvy to their advantages changing sails, i had assumed that twin groooves existed for that sole purpose (flying twin headsails). Asking more experienced folks i knew, i was assured that doing so would be highly detrimental to the foil, the sail's luff tape, or both. While some racing foils (such as Harken's snap-on carbo-foil) are clearly not intended for this treatment, others (such as Profurl's burly round extrusions) seem shaped to accomodate it.
What's the real deal? May twin headsails be flown from a double-groove furling foil without damage or serious hassles? Note: i'm definately not questioning whether twin headsails should be actually rolled up together; that sounds like a definate recipe for damaging chafe.