and a lot of very smart people fall on both sides.

But...as regards yesterday's game, most people who say that 1-run games are largely the result of luck (including me) would include ALL extra-inning games in that category.  The point being that after nine innings (or in yesterday's case, ten innings), those two teams were equal.  

Better teams will usually win more one-run games than other teams (especially better teams with good bullpens), but it's a very rare team that wins (or loses) a vast majority of their one-run games, and the same goes for non-one-runners of the extra-inning variety.

is that when one mentions record in one-run games, a point is trying to be made about performance under pressure: does a team have the intestinal fortitude to scratch out a run (or two) in the ninth if they're down by a run?  Can they keep from choking if they have a one-run lead in the 9th?

I don't know if any of that holds up --- if "better" teams perform , well, better in these situations than .500 or worse teams. I wouldn't expect there to be a huge difference, except to say that if you're taking a lot of one-run leads into the ninth and losing, you're probably not one of the "better" teams.

My curiosity is piqued, though: I'm curious about the number of one-run games.  If you laid out all of the teams from best to worst in total record and then graphed the number of one-run games (regardless of record), I wonder if you would get either:

A: something of a sine wave (i.e., the best teams play in few 1-run games because they more often win by more than one run; the worst teams play in few 1-run games because they tend to get clobbered), or

B: not (i.e., the best teams would be best because they win a greater than league-average amount of close games; any wins the worst teams get would be 1-run wins because they can't blow anyone out).

I'm assuming B.