Fausto Carmona's comparison group pretty much sucks regardless of his age

Fausto Carmona, allegedly
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Apparently, Fausto Carmona, the 28-year-old pitcher for the Indians is actually Roberto Hernandez Heredia and is 31 years old.

His older age may explain why Carmona peaked during his Age 23 season, when Heredia was actually already 26.

Let's look at comps for Carmona at his listed age vs. his alleged real age.
Over the last 4 seasons, Carmona has pitched to an 81 ERA+ over 645 innings. Based on his listed age, those were his Age 24, 25, 26, and 27 seasons.

Here are pitchers who, for Ages 24-27 pitched at least 600 innings and had an ERA+ between 76 and 86:

Rk		IP	ERA+	From	To	G	GS	BB	SO	ERA	Tm
1	Steve Arlin	670.1	85	1970	1973	110	100	305	416	3.95	SDP
2	Fausto Carmona	645.0	81	2008	2011	111	111	272	370	5.01	CLE
3	Zach Duke	664.1	85	2007	2010	112	111	172	330	4.90	PIT
4	Sammy Ellis	824.1	86	1965	1968	159	126	305	510	4.24	CIN-CAL
5	Dan Griner	608.1	84	1912	1915	120	75	184	219	3.60	STL
6	Jimmy Haynes	609.0	84	1997	2000	109	104	308	380	5.38	OAK-MIL
7	Russ Kemmerer	606.2	83	1957	1959	117	84	218	282	4.67	TOT-WSH
8	Lew Krausse	701.0	80	1967	1970	164	95	244	416	4.15	KCA-OAK-MIL
9	Randy Lerch	607.0	85	1979	1982	117	99	217	239	4.40	PHI-MIL-TOT
10	Art Mahaffey	651.1	83	1962	1965	123	99	243	406	4.34	PHI
11	Phil Ortega	754.0	84	1964	1967	136	119	263	438	3.96	LAD-WSA
12	Jim Pastorius	727.0	78	1906	1909	97	84	278	205	3.12	BRO
13	Doc Scanlan	644.2	85	1905	1907	88	76	292	314	3.09	BRO
14	Bill Steele	605.0	81	1911	1914	120	71	211	211	4.11	STL-TOT
15	Fred Talbot	627.2	80	1965	1968	131	96	255	330	4.10	KCA-TOT-NYY
16	Happy Townsend	773.2	81	1903	1906	107	83	263	330	3.37	WSH-CLE
17	Herm Wehmeier	628.1	84	1951	1954	137	78	311	270	4.78	CIN-TOT

Provided by Baseball-Reference.com: View Play Index Tool Used
Generated 1/19/2012.

Not exactly an inspiring bunch...Here's what these guys did for the rest of their careers after Age 27:

Rk		From	To	Age	G	GS	IP	ERA	ERA+	Tm
1	Steve Arlin	1974	1974	28-28	27	22	107.2	6.19	58	TOT
2	Zach Duke	2011	2011	28-28	21	9	76.2	4.93	80	ARI
3	Sammy Ellis	1969	1969	28-28	10	5	29.1	5.83	67	CHW
4	Dan Griner	1916	1918	28-30	15	6	65.1	2.48	113	STL-BRO
5	Jimmy Haynes	2001	2004	28-31	88	85	478.2	4.98	86	MIL-CIN
6	Russ Kemmerer	1960	1963	28-31	159	14	367.1	4.12	92	CHW-TOT-HOU
7	Lew Krausse	1971	1974	28-31	97	33	309.2	3.87	91	MIL-BOS-STL-ATL
8	Randy Lerch	1983	1986	28-31	67	9	129.2	5.14	70	TOT-SFG-PHI
9	Art Mahaffey	1966	1966	28-28	12	5	35.0	6.43	57	STL
10	Phil Ortega	1968	1969	28-29	36	16	123.2	5.31	56	WSA-CAL
11	Doc Scanlan	1909	1911	28-30	75	57	472.1	2.95	101	BRO
12	Fred Talbot	1969	1970	28-29	46	18	147.2	4.45	82	TOT-OAK
13	Herm Wehmeier	1955	1958	28-31	114	75	578.0	4.17	94	PHI-STL-TOT

Provided by Baseball-Reference.com: View Play Index Tool Used
Generated 1/19/2012.

Wow...not a lot of success here. None of these guys pitched past Age 31. Only Scanlan managed an ERA+ over 100 with 100 innings.

Now, let's look at Carmona's comps if he's actually 31 now, meaning that his last 4 years covered his Age 27 to Age 30 season. (Same criteria otherwise--at least 600 IP and ERA+ between 76 and 86):

Rk		IP	ERA+	From	To	G	GS	BB	SO	ERA	Tm
1	Dick Bosman	674.2	82	1971	1974	118	106	194	329	4.16	WSA-TEX-TOT-CLE
2	Dave Bush	660.0	85	2007	2010	118	112	194	439	4.92	MIL
3	Don Carman	648.1	85	1987	1990	179	88	263	380	4.47	PHI
4	Ownie Carroll	610.2	78	1930	1933	113	75	179	136	4.73	TOT-CIN-BRO
5	Kevin Correia	607.0	80	2008	2011	113	104	214	400	4.88	SFG-SDP-PIT
6	Alex Ferguson	637.2	84	1924	1927	124	83	261	216	4.93	BOS-TOT-WSH-PHI
7	Jack Fisher	744.0	85	1966	1969	146	106	196	379	4.09	NYM-CHW-CIN
8	Chick Fraser	1107.0	85	1901	1904	140	128	403	438	3.73	PHA-PHI
9	Ross Grimsley	748.2	86	1977	1980	127	115	218	208	4.33	BAL-MON-TOT
10	Andy Hawkins	701.1	84	1987	1990	119	113	283	314	4.52	SDP-NYY
11	Tom Hughes	811.2	85	1906	1909	129	91	238	434	2.87	WSH
12	Jesse Jefferson	607.0	82	1976	1979	117	82	256	284	5.00	CHW-TOR
13	Si Johnson	603.2	83	1934	1937	128	81	197	216	4.80	CIN-TOT-STL
14	Dennis Martinez	726.2	82	1982	1985	139	115	232	327	4.88	BAL
15	Harry McIntire	991.2	84	1906	1909	139	114	349	362	2.92	BRO
16	Darren Oliver	618.2	84	1998	2001	108	108	247	359	5.63	TOT-STL-TEX
17	Mike Scott	667.2	84	1982	1985	128	110	229	356	4.11	NYM-HOU
18	Claude Willoughby	639.2	83	1926	1929	166	73	315	127	5.54	PHI

Provided by Baseball-Reference.com: View Play Index Tool Used
Generated 1/19/2012.

Now this looks like at least a somewhat better group of pitchers. Here's how they did for the rest of their careers from Age 31 onwards:

Rk		From	To	Age	G	GS	IP	ERA	ERA+	Tm
1	Dick Bosman	1975	1976	31-32	55	39	263.1	3.83	93	TOT-OAK
2	Dave Bush	2011	2011	31-31	17	3	37.1	5.79	78	TEX
3	Don Carman	1991	1992	31-32	30	0	38.1	5.40	72	CIN-TEX
4	Ownie Carroll	1934	1934	31-31	26	5	74.1	6.42	61	BRO
5	Alex Ferguson	1928	1929	31-32	42	25	149.1	6.63	68	PHI-TOT
6	Chick Fraser	1905	1909	31-35	119	97	874.1	2.76	100	BSN-CIN-CHC
7	Ross Grimsley	1982	1982	32-32	21	0	60.0	5.25	77	BAL
8	Andy Hawkins	1991	1991	31-31	19	17	89.2	5.52	71	TOT
9	Tom Hughes	1911	1913	32-34	101	65	548.2	3.48	93	WSH
10	Jesse Jefferson	1980	1981	31-32	56	24	205.1	4.65	87	TOT-CAL
11	Si Johnson	1938	1947	31-40	207	100	868.1	3.98	90	STL-PHI-TOT-BSN
12	Dennis Martinez	1986	1998	31-43	377	319	2231.1	3.34	119	TOT-MON-CLE-SEA-ATL
13	Harry McIntire	1910	1913	31-34	58	39	349.2	3.63	85	CHC-CIN
14	Darren Oliver	2002	2011	31-40	422	52	714.0	3.93	116	BOS-COL-TOT-NYM-LAA-TEX
15	Mike Scott	1986	1991	31-36	172	171	1183.1	3.07	117	HOU
16	Claude Willoughby	1930	1931	31-32	50	26	178.2	7.40	71	PHI-PIT

Provided by Baseball-Reference.com: View Play Index Tool Used
Generated 1/19/2012.

Yeah, that's somewhat better. Dennis Martinez and Mike Scott pitched a lot more innings at a good level, and Darren Oliver is still going strong. But there were plenty of flame-outs too, with more than half of these guys pitching no more than 2 more seasons.

The basic lesson here is garbage in, garbage out. There aren't too many pitchers to put up such a tough 4-year stretch and then discover a lot more success later.