Pitcher A: 3.00 ERA 3 innings
Pitcher B: 3.20 ERA, 230 innings
Pitcher A: 5.30 ERA, 120 innings, 110 Ks, 80 BBs
Pitcher B: 3.25 ERA, 125 innings, 96 Ks, 21 BBs
You can prove a whole lot of nothing throwing out random stats.
Pitcher A: 191.2 IP, 5.07 ERA, 47/147 BB/SO
Pitcher B: 191.1 IP, 3.90 ERA, 89/221 BB/SO
What does IP tell you there? And what is the defining stat that makes you like pitcher B compared to pitcher A?
It's ERA. If you're going to glom onto one pitching stat (not including advanced metrics), ERA is the obvious choice. Innings Pitches tells you nothing about quality of pitcher unless you get to the far end of the spectrum (if a guy throws 230+ IP, you know he was at least an effective pitcher, if not a great one). Hanging on to this notion that IP is the most important pitching stat is ridiculous. Just give it up.
Besides, declaring one statistic the best is a silly notion in the first place. Why would anyone in their right mind choose one statistic when you have hundreds available to you?
I think what this all comes down to is what you expect from your starting pitchers.
Do we expect our pitchers to be dominant and able to shut teams down and virtually win games on their own? Or do we want pitchers who can just keep the game close, who can eat up innings, and give the offense a chance to win the game by scoring runs?
Obviously, it depends on what the rest of the team looks like. If you have confidence in your offensive capabilities, you are more willing to accept a rotation of #3 & #4 starters. If you don't have confidence in your ability to produce runs, you are more likely to demand/need better starting pitching to compensate. My guess is that Twins feel good enough about their offense that a rotation of dependable if unspectacular starters is OK for them. Time will tell if we got that (or if their analysis of offensive capability is accurate).
Obviously, you'd like to have both good pitching and good hitting. Doesn't happen that often in real life, though. When it does, it usually means World Series.
But I think you're getting at an important point that I've preached often. A pitcher is only injury-prone until he's not, and vice versa. Carl Pavano's a fine example -- he's gone back and forth about four times in his career. Pitchers with a relatively clean bill of health suffer major injuries all the time, it's the name of the game.
Major League Leaderboards » 2012 » Pitchers » Dashboard | FanGraphs Baseball
You can play around with what stat you'd like to rank pitchers by, WAR, ERA, IP, xFIP, whatever.
It's interesting to note, and not surprising that IP will correlate with what most of us consider good pitchers and bad pitchers at the extreme ends of the spectrum. However, for a massive number of pitchers, it doesn't correlate at all. Jarrod Hudson had a 3.47 ERA but only threw 187 IP, putting him in the bottom 3rd of the majors of qualified pitchers in IP. There are a ton of pitchers like this: Samardzjja, Lynn, Hellickson, Moore, Hudson...
How can IP be the most important stat if there are pitchers like this in the bottom of the league in IP? Meanwhile Clayton Richard and Justin Masterson threw over 200 IP. I'd take any of the pitchers I named above over them for last season's performance. How can that be considered if IP is the most important stat?
your thoughts about ERA here last fall. I agree that we should not be closed-minded and focus on one stat for any player. But, for pitchers, ERA would be the one to separate those with equal IP
"I think about baseball a lot, and ERA is the MOST important stat for a pitcher in my opinion. Your starter's ERA is what you're facing, on average, as an offense (until or if the starter exits, obviously)." - me.