We already tried that. Remember the late 90's? IE4/5/6? Microsoft via Windows/IE are still in the best spot to push the proprietary web. They may have only 50% market share but that's quite an advantage over 15% for WebKit and 25% for Firefox unless they combine forces. As long as Windows remains dominate on the desktop ~90% of people can simply click on IE to access an IE-only website. Before too long they'll forget Chrome or Firefox ever existed. Few sane developers will exclude 50% of the market.
I highly doubt that people who have tried chrome or Firefox will forget it existed. they may not use those browsers at work right now. but corporate apps are changing rapidly towards true open web-standards-based browser solutions. and as that transition accelerates its hard to see how the fastest browser doesn't win. my money's on chrome.
