The first time I played, I did it without a caddy as a friend and I were on a late, locals-only tee time, playing with the Links Superintendent and the Head Greenkeeper.
It actually ended up as a match with us against them, so we had to get our advice from out opponents.
The next day, we had caddies for our fourball, and everyone got the perfect caddy for them. Mine was a pre-med student who was headed to Oxford after St. Andrews, and his intellectual approachto teh game was great.
My wife got a retired chemical engineer with short legs who suited her bad knees,
My friend got an American kid from Harvard, who was the only caddy who he could understand on the whole two-week trip.
His wife drew the captain of the St. Andrews U. golf team who was perfect for a 30+ handicapper who hits it 120 yards off the tee. Some of the lines he gave her off tees were inspired, and when she drove it into a deep, small pot bunker on 12 he said, "Tha' looks like a hand wedge eh, Ma'am."
I wouldn't consider trying to figure the lines of play on the course without any help, but you don't really need a caddy for every golfer.
K