Why Apple needs a "headless" Mac

Chris Seibold on AppleMatters recently wrote why we won't see a "headless" Mac. I recently posted why I Apple needs a sub-$1000 Mac. I expand on that a bit in the comment, reproduced here, that I posted on AppleMatters in response to how unlikely they view the "headless" Mac:

But I disagree with your conclusions. The point of a low cost Mac is not to maintain profit margins, those will have to be sacrified somewhat, but to grow market share at the expense of profits. Growing share diffuses one of the main criticisms from PC partisans, and it's also a defensive strategy as Linux desktop share grows. If Apple can get their share above 5%, the positive feedback loop of share driving software development decision efforts will guarantee the continued existance of the Mac platform. Apple needs to maintain existing app develeopers and expand the pool. A large percentage of growth in the PC market is coming from the low-end, and though a $1299 iMac is close, sub-$1000 is the magic number. I am not saying Apple is doomed if they don't get into the low-end market with a more PC-like headless machine, but I don't see them achieveing significant share gains without it.