Dear guy at the pool that I've never seen,
I'll just jump right to the point. I'm sorry you seemed disappointed with me when I took issue with the 3rd guy who jumped in our lane. It's unfortunate that you and I had to have a bit of a heated conversation at the far end of the pool while the infractor** got in at least 100 yards in a wide open lane.
** Let it be clear I am apologizing to you and only you, I feel my points about the above referenced "3rd" gentlemen a/k/a "the infractor" are still valid.
As I tried to communicate to you in the pool, you where a pleasure to swim with. You did all the correct things that pool etiquette dictates - waited for my previous lane mate to leave the pool, confirmed with me between my sets that you had joined me, and swam a great line back and forth in your half of the lane. In short, you where the perfect lane mate and I could ask for no more.
I am, however, a stickler for etiquette. When a 3rd person wants to join a lane, I believe that permission should be granted by mutual consent of the current 2. It's unfortunate that the infractor did what he did. I'm guessing that he didn't even ask you, either. In fact I'm not guessing - The point was made quite clear by what he said to us. His comment "sorry dudes" is quite revealing in two ways. First in that it suggests that he jumped right in without any permission and second in that he knew it was wrong.
That all said, I can't fault you for your position. I too am generally as generous as I can be, especially at the pool. Our local pool is crowded, and I do want everyone to get a work out in. It's just unfortunate that this guy's behavior rubbed me the wrong way - much to your chagrin, and the issue shifted from us v. him to you v. me.
The truth of the matter is that I prefer to not circle swim. This is because I suck at swimming. I am afraid that my lack of speed will be a detriment to you and your workout in the end. If asked by a 3rd to circle, I will always say yes, being careful to communicate my concerns about my abilities and the adverse affect it may have on my lane mates. Forewarned in forearmed, I like to say. My workout will probably be fine as the slow guy is not waiting for anyone. But you where clearly faster than me. And since you seemed a little too generous to have your workout handicapped by a circular pattern (and given the infactor's behavior), I ended up feeling compelled to vote for you by proxy. Perhaps that was not my right.
Anyhow, perhaps we will swim again under less trying circumstances in the future.
PS If you sense sarcasm in this letter, it is intended. However, it is in no way directed at you. Rather, I thought a bit of dry humor would improve the quality of my message since at the end of the day the whole thing was pretty funny.