Mark:
The greater the width (as much as a property can provide) the greater the degree a player will have to have in overall shotmaking dexterity. When courses narrow themselves beyond reason you have a reduction in the overall decisions a player must make. It just becomes defensive golf over and over again. I like the Mckenzie, Tillie and Ross beliefs that you should give the player a fair amount of room off the tee.
Too many courses from my travels, particularly in the Northeast and Midwest overly fall prey to the belief that added rough / narrow fairways will add to the demands of their course. All I see with such a situation is the reduction in the creativity that was likely envisioned by the architect. Golf is about playing angles and those playing angles are not always dead-center right in the fairway. Shaping shots is fundamental to the game.
Take a course you know full well. How much rough / narrow fairways does Lehigh need? Given the preferred angle into the target area (depending upon pin location of course) you must find those areas to really take advantage of your scoring opportunities.
Courses with 20-25 wide fairways are overly constricted and do nothing more in most cases for boring and tedious affairs.
I say unless you are holding some sort of event of consequewnce (could be a club championship or higher on the charts) the need for rough should be carefully examined. I well designed course has many defenses and rough should be a part of that equation when it is reasonable in height and applied in such a way so that fairways are not overly consticted.
One last item -- the narrower you make a course the greater the time spent looking for lost balls and the accompanying result ... a S-L-L-O-O-O-W-W-W-W march to the 19th hole.
Hope this helps ...