As far as I'm concerned, Europe won the Ryder Cup (rather than "retaining" it). To retain a Ryder Cup, you merely have to tie your opponent after winning the cup the previous time. However, Europe outscored the United States 14-1/2 to 13-1/2.
I recognize that Tiger was probably sleepwalking that last hole; but, I also think the Europeans deserve more credit for getting to 14-1/2 rather than 14.
I also think, because of this distinction, it would have been tremendously sportsmanlike if Europe had conceded Tiger's putt rather than giving him the opportunity to miss it. But, I also recognize that Europe may have still been so distracted by their tremendous comeback that they overlooked this.
C