You're clearly correct - 95% market share proves their incompetence.
Not sure why I have to point this out, but you weren't commenting on their market share (though that's always a safe (if tired) position to retreat to, eh?) - you were commenting on the use of their cash. And the use of their cash has been pitiful at best, as any shareholder can tell you, burning boatloads of it in a desperate attempt at cool. The Xbox and Zune debacles weren't enough, now they're paying people to use their search engine. Now there's confidence in your product! Not to mention their sure-to-be-doomed wannabe Apple Stores. It would all be funny if it weren't so sad.
You may want to check out the graph of their stock price over the last 5+ years. Can you say flatline? Not a ringing endorsement of their reinvestment strategy. Not that logic will appeal to you if it's to Microsoft's discredit.
I'll take Apple's cash management over Microsoft's any day of the week.
So, 95% market share means that the rule of the average is true and nothing else. Go figure.
The WinBots love to trumpet their massive market share while proclaiming Apple users to be sheep. Yep, go figure.