JJ:
I think that's a normal perception because 11, 12, 13, 15, and 16 all have water, so a train wreck is just a bad swing away. Plus, 13 and 15 can produce a 3 as easy as a 7. So once you get past 16, there's less of a chance for big swings in score. 17 and 18 are not easy birdies and not easy to double either.
The 1998 Masters may be remembered somewhat for Freddie's 13th and 15th holes, but 17 and 18 are where O'Meara won it.
2003 came down to Weir's 6 footer on 18.
2004 came down to Phil's putt on 18.
And obviously last year, the biggest dramatic and memorable moment was on 16. I know first hand because I was standing about 50 feet behind Tiger when he chipped in.
But the bogeys he made on 17 and 18, DiMarco's tying par putt, and the playoff on 18 made for great theater as well, and ultimately decided the outcome.