I think you would enjoy The Luck Factor, a book about which I have previously written (http://jiggery-pokery.livejournal.com/92688.html). It backs up your theory with some more thought; it provides an excellent and plausible rationale for optimism and the ways in which optimistic people tend to perceive themselves as being luckier, if only because they perceive any particular set of events to be lucky in a fashion that pessimstic people would interpret as having been unlucky.