Shifting Problem Update
Our local dealer had the XLR for several hours yesterday and found nothing. The Tech, Service Rep and Service Manager all three test drove the car and none experienced the shifting problem.
Like any random or intermittent problem, it won't happen when they are checking it out. It is a "once per day" problem, so we'll just log when and under what conditions it is observed. If anything, we've baselined the concern and will monitor it to see if it gets worse or more frequent.