As someone who actually watched the series and almost every Spurs game this season....
Spurs played like dog shyt most of the series, they really played some of their worst games of the season that series with horrible turnovers after turnovers. Plus the Mavs were red hot, hitting contested shot after shot. If Carter doesn't hit the buzzer 3 in GM4, Spurs go back home 3-1 and close out in 5. Instead he hits shot and it's extended to 7. Spurs only complete game was GM7 and it was a monumental ass whooping
Again, from someone who actually watched the Spurs this season