At the US Open at Merion a couple of years ago, my son and I sat on the second tee and watched player after player go left into heavy rough. As soon as the ball landed, a fleet of spotters went to work, scouring the grass and almost always finding the ball before the player and caddy arrived. In spite of heavy grass, there was virtually no risk of losing the shot. It was obvious that no one was worried about not finding the ball.
In fact, most players didn't even seem to watch their shots land. They knew that they wouldn't be responsible for finding it and that the volunteer fleet would take care of it.
I haven't visited Erin Hills, but it sounds like players will reap massive benefits from the spotter and marshall crew, especially on holes like #8. Unless it carries into the high fescue, losing a ball seems just about impossible (which is true at every one of these tournaments).
This isn't the case, however, for every recreational (i.e.g "real") round I've ever played, however. Architects rely on the threat of a lost ball to force decisions from players. Line of play, especially on blind shots, becomes more important when you know a poorly struck shot might never be located.
At Ballyhack, holes like #4, #6, #12, and #15 cause tension because tee shots played offline (and/or not followed visually) can be lost. Tracking the ball and making an educated guess about its resting spot are really, really important.
On a Ross course during a Virginia State Open qualifier last week, my group looked for a ball more than thirty yards from where it was eventually found by a passing spectator. It hadn't been watched carefully enough and, apparently, it hit a mound and shot sideways. In a major event, its location would never have been in doubt.
What notable holes lose some luster or teeth when a dozen spotters are plopped in place?
What holes (and/or courses) utilize the threat in the most effective way under everyday conditions?
Imagine a US Open at Erin Hills with no stands, no spectators, and no marshalls. Top ten or twenty finishers would shoot the same score, but, for a good number of players, it would make the place vastly more difficult.
WW