The pitching staff for the Orioles is mostly decided to start the season, but things look like they'll be in flux all year long. The guy who'll end up being the team's best starting pitching could be the Opening Day starter, or it could be someone beginning the year in the minors. A number of pitchers should end up getting starts throughout the season, and I wouldn't expect any one in particular to go for more than 150 IP (someone probably will, but it's anybody's guess as to who right now). That makes these projections really sketchy:
So many of the pitchers having similar FIPs is unintentional - I did strike-out, walk, and groundball rates for each, and that's what they came out to, more or less. It's been what I've said a few times this off-season - the O's have a lot of depth when it comes to #4/5 starters. If one guy gets hurt, the drop-off to whoever is next in line shouldn't be too severe (it's just that they all are kind of mediocre). Alfredo Simon* and Dana Eveland** may not end up pitching for Baltimore this year, but you can pretty much fill in "Miscellaneous Pitcher" for them and the results should be in the neighborhood. It's an almost certainty that there will be some O's putting up below replacement level innings, but guessing who that is in advance is a little trickier (just like some starter will probably post an ERA below 4).
* Not that Alfredo Simon is a top flight pitcher, but I don't understand just letting him go. He could very easily be the team's best starting pitcher (if healthy), and showed improved control even while moving into the rotation last year. At almost 31 years old it's not likely that Simon would be a part of the next good Orioles team, but I don't really understand the reasoning for giving away a potentially useful arm. If they end up trading him that might be a different story, I suppose, thought I don't see them getting more back than they gave away for Dana Eveland (and a Simon for Eveland swap does not sound enticing).
** They traded some young players for a mediocre pitcher, and then designate that pitcher for assignment a few months later. Who could have seen that coming? Taking chances on freely available talent is good - if it doesn't work out, you don't lose anything. Trading assets for what should be freely available talent is less good.
A 4.42 team FIP would be an improvement over the 2011 club's 4.67, but the second worst team in the majors last year (the Reds) was still better (4.37). It's a mighty bad pitching staff. Plus, given the O's below average defense, the team ERA should be even worse. Hopefully they can give up less than 800 runs this season.