alosso: Apparently, these become active when there are no pictures towards the flag for the next shot. I've had a ball disappear in flight there ;)
Exactly.
A while back, in practice mode, I tried hitting into an adjacent fairway on one course to test if it would give me a shot (it may even have been Oakmont). Even though the ball clearly landed in the fairway each time, it came up as "out of bounds" and resulted in a lost ball. Obviously, I did the test with starter balls.
So unlike real life, there are times that adjacent fairways are not going to be in play.