Two statistical nuggets:
Felix Hernandez tied Tom Seaver's major league record with 13 consecutive starts pitching at least seven innings and allowing two runs or fewer.
Adam Wainwright has allowed zero runs in 10 starts this season, three more than any other starter.
So, which feat is more impressive?
To put Wainwright's nugget in context, since 1980 only three pitchers have had more than 10 no-run starts, all with 11: Dwight Gooden and John Tudor in 1985 and Cliff Lee in 2011. Eight other times a pitcher matched Wainwright's total of 10: Roger Clemens (1997 and 2005); Pedro Martinez (2000 and 2002); Clayton Kershaw (2011 and 2013); Greg Maddux (2002); and Chris Young (2007).
(The Baseball-Reference Play Index goes back to 1914 and five other times a pitcher topped 11: Pete Alexander in 1916 with 16, all complete game shutouts; Sandy Koufax in 1963, Dean Chance in 1964 and Bob Gibson in 1968, all with 13; and Alexander again in 1915 with 12.)
Anyway, in a way it's a question of consistent dominance versus dominance mixed in with a few bad or mediocre starts. Which is more valuable? But in evaluating the context of each pitcher's individual performance, you could conceivably factor in things like the strength of the opponent, the park and the pitcher's performance (strikeouts, walks, hits). Bill James actually just had a long series of articles on this where he examined every start of a pitcher's season for each of those areas (plus the run context of the season). Each start was then graded on a scale from 0 to 10. You can then use the data to break down each pitcher's season in total. It would be fun to compare Hernandez and Wainwright, but the numbers aren't publicly available.
Baseball Prospectus used to have a stat called support-neutral win-loss record, which assessed each pitcher's projected win-loss record given his innings and runs for each outing and average run support, but I don't see that on their site. (Felix has won just seven of his 13 starts, no fault of his.)
Interestingly, Hernandez has just two zero-run starts this season. But he's allowed more than four runs just once -- six against Houston on April 21 (and just two of those were earned) -- whereas Wainwright has had games of seven, six and six runs.
For the season, we can use a stat like to WAR evaluate each pitcher's overall performance. Felix leads Wainwright in FanGraphs WAR, 5.5 to 3.5, while Wainwright leads in Baseball-Reference WAR, 5.3 to 5.0. Felix leads in Baseball Prospectus' WARP, 4.0 to 3.3.
So which feat is more impressive? One thing about allowing zero runs: You're almost guaranteed to win the game. And, indeed, the Cardinals are 10-0 in those 10 games.
On the other hand, Felix has a chance to do something no pitcher has ever done -- 14 consecutive great starts.
What do you think? I'd probably give the slight edge to Wainwright's 10 scoreless games ... although the edge to Felix for the better overall season.