I move that it is adopted as a mando that anytime you have a shotgun start outside of a tourney that you MUST let a group with fewer players (or equal amount in some cases) then your own play through if they meet you at a tee pad within the first two holes you play upon start. I have been burned by this and have seen this happen too many times to mention.
I love doubles and organized play don't get me wrong. I know that you have to spread out on the course in order to get in a round in less then 10 hours. My problem is that you (we) are cutting people off on a public course. Just as we have a round we want to play smoothly, so do they. So the foursome that just walked out to hole 12 to start their round is blocking the group that's putting on 11 from finishing up their round with the same tempo they have been playing since hole 1. If two players decide to walk out and play the hole you're about to walk up to drive on you'd flip! Casual players are not in your doubles match and don't need to be effected by it.
If it's a foursome, allow them play through on the hole you're both standing at at the very least. If you're cool and they walk up to drive as you're playing your upshots, wait up and let them play through the next hole. Any more then that you don't have to offer, you're now in the flow.
You never know, the players you cut off and pin down could be great people who would fit in well next doubles match. Not showing some common courtesy may sour them to the group play experience.
Just a thought.