The problem for me with those arguing that Jobs was smart to not allow the clone market is this: opening the clone market WOULD NOT be competing with the PC market. This is fallacious. The fact is, opening the clone market would have been competing for the _Apple Market_ and that's the main reason why Job's didn't enter it; I believe he feared Apple couldn't compete. Smart? Depends on whether he was right or not.
IMHO, if he'd followed a very simple business model, he could have increased Apple's marketshare considerably: open the market, but maintain the "gold standard" for what Apple hardware should be. Then, let anyone who wanted to create clones be responsible for their own hardware and wash Apple's hands of their competitor's hardware. In other words, clone competitors can copy Mac hardware but if they introduce anything not "blessed" by Apple, they are responsible for it. Customers should go to them, not Apple.
This model would have opened competition, but kept Apple in the leadership position by allowing them to define what Apple hardware ought to be. Anyone that wanted "True Mac Hardware" could have it by going to Apple while those of us who prefer affordable/reasonably priced hardware could go elsewhere to get it. Nobody, but those who provided that hardware and software to support the non-blessed parts, would "tarnish" the holy Apple name.

Yea, this probably would have cost Apple _some_ sales, but I expect they'd make it up in royalties and licensing.
Instead of surfing the entire desktop market, Jobs chose to be king in only a very small part of it. I'm not so sure that's all that smart. Not sure it's stupid, either, but I personally think Apple would have been better off fully appreciating the nature of the market rather than cornering one tiny part of it.
My two cents, anyway...