Not sure I agree with the arbitrary yardage you have come up with in determining appropriate etiquette. My take on it is that if you are one of the many fishermen in the park that sticks close to your car and doesn't hike over 1/4 mile to fish, then by all means crowd together as close as possible with other folks doing the same. This leaves some semblance of remoteness for others who really want to "get away" from folks. Even away from the road, there have been too many fishermen in recent years as far as I'm concerned. I didn't even purchase a license last year for the park and know of others who did the same, just to give the park fish a break. Some days I've driven by and thought perhaps the park ought to do away with fishing altogether. As far as etiquette is concerned, use some common sense - there will be plenty of others around who will not.