Jim Franklin,
Before understanding the comment, I think you have to have your friend define what he meant by "An Old Man's Course"
Certainly, from the back tees, Shinnecock Hills is harder.
They added back tees to challenge the best players in the World.
That's a choice Shinnecock made when they solicited or were solicited for the U.S. Open.
NGLA has added back tees, randomly, to retain the relevance of the architecture interfacing with the golfer, members and guests.
Now, with the Walker Cup in 2013, they may add additional length, limitedly, to challenge a small select group that may be the best Amateurs in the US and UK.
Those two courses have distinctly different playing personalities.
One isn't better than the other, although one may be prefered over the other, depending on your tastes and mood.
When I think of those gerrymandered composite courses, I wouldn't take one hole from either course and replace it with another.
I think they're perfect, or close to perfect, just the way they are.
Under tournament conditions, when NGLA is F&F, you let me place the hole locations, or just let me select the hole locations from previous qualifying events, and I'll bet your friend anything he wants that he can't shoot his handicap, so ask him to define "old man course" for you, and start getting a syndicate together because we're going to make a fortune.