Copied from the other attempted U.S. Open thread:
The regulations for the U.S. Open (click on the “Championship Regulations” link on that page) say that the tournament committee may authorize carts in certain conditions, but does not say what they are. It also has the “Casey Martin rule,” where somebody meeting the AADA definition of a walking disability may apply for permission to use a cart.
USGA Rules of Golf rule 6-7 says that the tournament organizers may set “pace of play” guidelines; the first breach is a 2-stroke penalty, and the second is a disqualification. Apparently, Furyk and McDowell had received two warnings; after a third warning, they would be subject to a “shot clock.”
I have seen carts used on a course where there was a long distance between one green and the next tee. This was at the TPC Sugarloaf course in Atlanta.
They often take the players and caddies on carts to start a playoff.