Considering your best-ever score on each hole on a course brings you into astronomical odds for that hypothetical perfect round.
Imagine a hole that you "2" only 1% of the time---presumably with a 100' putt after a great drive. If there are 3 such holes on your course, the odds of getting all 3 of them are, what, a million-to-one? And that's before factoring in the other 15 holes.
It might be more practical---and eliminate the aces---to assign to each hole the best score you get, say, 10% or 20% of the time. This is where you walk off the course after your best-ever score and think, "I could have done even better if I'd just got #7 and #11, which I know I can do."