If you've played shot many times before, then this can't be the first time you have been OB. There's a fine line between playable and OB when you try that......I watched your replay 5 or 6 times, and it looks like you just went a whisker too far left.
The same thing happens if you play to the right-hand fairway on Oakmont #4. It will sure look good, but too much to the center of the fairway and you find yourself OB.
Both high-risk, (slightly) high-reward shots.