I actually think 75% of the pga tour golfers play slow already. I think 5 hour rounds at Augusta are pretty much standard, least it feels that way. Get to Amen corner and it might take groups 20 minutes to play hole 12.
wind
*backoff*
wind
*backoff*
wind
*backoff*
repeat.
wind
*backoff*
wind
*backoff*
wind
*backoff*
repeat.