Sam,
Yes, it is for the trailhead, but you still have to camp somewhere. Even when you get the permits, you cannot camp as a single group in one place with that number- you must separate into two groups of ten or less. My point was to get the permits as two entities and also plan to camp some distance apart. You don't want some zealous ****** coming up and telling you to all move, or issuing citations.
Also, there is a guaranteed permit ratio of 50-50 mail-in reservations to next day walk-ups. (Some trails 60-40.) There is always the ability to get a reservation for the next day- just get to the valley a day early and hang out at the backpacker campsight. He might get permits for ten in one first reservation this week, and the late joiners can almost be 100% assured of also getting a permit for the next day when they walk up later- right before the actual hike. My point is that it may be better to get two separate group permits under separate names for the same trail- even if they may have to be obtained at two separate times.