The correct way to handle the overseas cash is to invest it in doing more R&D overseas, and indeed Apple is gradually doing that. It would be nice if Apple could bring back that money to do the R&D in the U.S., but paying that huge tax bill just doesn't make sense for shareholders.
What Apple management knows, and you seem to be missing, is that Apple is in a very volatile business. They are always a misstep or two from being back in the red. Remember, in 2007 Motorola, Nokia, and RIM were all doing great. Now they are all going under or sold. Apple management also hasn't forgotten the days of having to grovel before Bill Gates. Apple needs an insurance policy and keeping their cash around $100,000,000,000 is a good one. Their current dividend, buyback, and investment programs are keeping cash pretty stable- time to leave well enough alone.