I don't want to give the wrong idea with this post. My head says that the Braves' 5-1 start doesn't necessarily foretell greatness (or much of anything). Ultimately, these six games count the same as six games in the dog days of August. Practically every team wins 5 out of 6 at some point (even the 2003 Tigers did it once), so this is likely just a quirk of timing. It really shouldn't change our expectations for the team.
That said, I thought it would be fun to look at which other Braves teams started 5-1*, and where those teams ended up. Suffice to say that the results were interesting.
* Two Braves teams started 6-0: the 1994 team, which started 13-1 and was 68-46 but trailing the Expos at the time of the strike, and the 1982 team, which famously started 13-0 and held on to win the NL West with and 89-73 record before being swept in the NLCS.
Let's go through the 6 teams in reverse chronological order:
This team, the penultimate of Bobby Cox's career, started the season winning 5 of 6 against the Phillies and Nationals. Of course, they promptly lost the next 5 games, and were similarly inconsistent all year. They won 15 of 17 in September to get back into the Wild Card race but finished on a 6-game losing skid.
Final Results: 86-76, 7 games out of 1st in NL East, 6 games out of Wild Card
This team started 5-1 against the Phillies and Mets, then won their next 2 against the Nationals to reach a 7-1 record. Unfortunately, they were just .500 for the rest of the season, never really threatening to win a mediocre division. (And that is despite trading 17 future All-Stars at the deadline for Mark Teixeira.) Still, this team did finish with a winning record, just like every other team on the list.
Final Results: 84-78, 5 games out of 1st in NL East, 6 games out of Wild Card
Coming out of the strike, this team started 7-1 against the Giants, Dodgers, and Marlins, and never really stopped winning. With a pitching staff led by an at-his-peak Greg Maddux (not to mention Tom Glavine and John Smoltz) and a lineup featuring David Justice, Fred McGriff, and some rookie named "Chipper Jones," this was a truly special collection of players. I'm sure you remember how it ended. (If you don't, or if you just want to feel good for the rest of the day, click that link.)
Final Results: 90-54, 1st in NL East; won World Series
After losing their first game, this team won the next 7 against the Reds and Padres. The first half of the season went quite well; as of August 13th, the Braves had a 6.5-game lead in the NL West and Dale Murphy was well on his way to his 2nd straight MVP award. Alas, a 5-14 swoon allowed the Dodgers to pass the Braves, who ended up in 2nd place with no Wild Card to bail them out.
Final Results: 88-74, 3 games out of 1st in NL West
This team started 6-1 against the Giants and Reds. Behind great years from Hank Aaron, Phil Niekro, and Rico Carty, they led a tough division most of the season. They went 20-6 in September to hold off the Giants and proto-Big Red Machine Reds. Unfortunately, they ran into the buzzsaw of the Miracle Mets in the NLCS and got swept. Still, this would stand as the best Atlanta Braves team until the 1990s.
Final Results: 93-69, 1st in NL West (by 3 games); lost NLCS
From the start of the 20th century until 1969, the Braves franchise only started 5-1 once (the Boston Braves were awful for a long, long time). That one time was 1957, when the team won 9 of its first 10. With Aaron, Eddie Mathews, and Warren Spahn all at the top of their games, they outclassed the rest of the NL, winning the pennant by 8 games. They then edged the Yankees in a classic 7-game World Series, winning the Braves franchise's only title between 1914 and 1995.
Final Results: 95-59, won NL; won World Series
So there you have it. Of the six Braves teams to start 5-1, all were at least pretty good, three made the playoffs, and two won the World Series--the franchise's only two World Series titles since 1914. That's a pretty good track record, with not a fluke in the bunch.
On the other hand, the 2007 and 2009 teams weren't exactly memorable, especially compared to the fantastic teams that preceded them or even the pretty-darn-good teams that came after them. The 1983 team likewise couldn't finish the job.
I know I was surprised to find that none of the terrible Braves teams (and there have been a LOT of terrible Braves teams) lucked into a 5-1 start. I was perhaps even more surprised that none of the 1996-2005 teams started 5-1. That's probably just coincidence, though. There's no reason to think that good starts are any more meaningful than good middles or good finishes.
Objectively, starting 5-1 doesn't mean that this year's Braves team is more likely to win the World Series. Well, it is a little more likely--they are now a game or two ahead of where we might have expected them to be, and that's not nothing. Winning 90+ games is now a little easier than it was when the team was 0-0.
In short, these 6 games haven't given us much new information, so there's little reason to raise our already high preseason expectations. It's hard to suppress excitement, though, at any little stat that puts this team in the company of the 1957 and 1995 teams. My head knows it doesn't mean much, but my heart is downright giddy.