One more point: One thing that is stopping Apple's share price from going up is its massive cap size. Its over $400 billion dollars. When it was $700 a share it was at over $600 billion. That could simply be too much capital for the financial system to support for one stock. But by separating the stock you would not need additional cash.
Current price: $450 share = 425 Billion
Pref Stock: $250 share = 220 Billion
Total Cap: 645 billion
But lets remember that the Pref Stock does not require any new cash from investors. The net cash paid out for the stock is still $425 Bil even though the combined Market Cap is now $645 Billion