Brent,
Tough call between A and C, but I think I would choose A.
One issue is that single row can be limiting for what you want to do, especially in times of drought, unless you commit to letting all the grass go dormant/die just the same. That may be what I would have liked to see from Pinehurst in pushing the envelop further--letting the centers go almost as much as the outsides. Perhaps the concern there was the back to back tournaments and the wear issues, and maybe we do see something more aggressive the next time around. The concern might have also been it being too firm throughout and too many balls running into the scrub. I totally understand this for resort play (the single line making good sense here), but the pros might not have needed the line of velcro since they handled the native quite well. (side note: Anyone arguing the rough was too easy--there were three players under par. Your argument is invalid.) Overall, I think the single row works for Pinehurst because it ensures that there will always be nice natural transitions into the native areas, no matter who is in charge, and that is a big key point of this recent restoration.
Outside of Pinehurst, I'm not so sure. On a big wide open course, it hardly makes sense to me. There are some open old farmland type courses with single line irrigation around Southeast Michigan that we used to play in the heat of August, and everyone would aim away from the fairway, bombing it down the hard pan rough for an extra 80-100 yards of roll. Obviously, it's not really working there, unless you are a big fan of inverse golf.
The important part is to take what Pinehurst is doing in spirit and discontinue irrigation throw inside the areas of regular maintenance. That could be one head, 3 heads, or 8. It doesn't matter as long as those transitions to the native boundaries are made properly.