I just stumbled upon this thread...
First-off, to echo many here, this is really terrific work and worthy of any professional historian/writer...being that I am on the north side of 50, I lived through many of these dates and these vignettes help me remember a lot of what I had forgotten.
Second...some comments on the already posted days:
August 6, 1986: Growing up an Orioles fan in the 70s was unique (in my experience). The Orioles having a winning team and, if not making the playoffs, always being right there at the end was just the way it was. It was expected just as it was expected that the nights would get colder and the days shorter. It's August, so the Orioles must be making a run towards the pennant. So when you are living through an epic era of success, you don't appreciate how good you have it and it it is hard to know when it truly all ended. But end it did and with a little perspective, 8/6/86 is about as close as any date to mark it. (I personally think the end was started when a terminally ill Edward Bennett Williams instructed his front office to go spend money on the free agents at the expense of the farm system somewhere around 1984/85 in a bid to get him one last championship before he died. But your date works for the reason you stated with regards to the records.)
The Davis trade. Truly an epic failure....but to me, that was the result of an earlier, more costly mistake...
Eddie Murray. If you don't trade Eddie after the 1988 season (and I am sure this date will make the list), presumably you don't need to trade for Davis in 1991. It goes without saying, but Eddie was one of the truly great Orioles...both on and off the field (I believe he still to this day contributes to some Baltimore-based causes). Maybe had social media been around back then, we would have gotten a different perspective of the man. As it was, a petulant media (led by a talk radio host) decided that Eddie would be the scapegoat for all the ills of the Orioles organization in the late 80s and proceeded to run off a 1st ballot HOFer (pre-steroid era), and one of the greatest, if not THE greatest, Oriole leaders to ever be in the clubhouse. The list is a short one: there is Frank and Eddie..and let me get back to you...there is a reason in my mind that all the Orioles' championships were won shortly after these men arrived in the clubhouse, and none thereafter. Brooks is my favorite Oriole. But if Brooks is #1, Eddie is #1A.
Can't wait to read the rest!!!