You are putrid
"YEAH HI, I'M A NATIONAL LEAGUE PITCHER AND I WAS LOOKING TO ENHANCE MY WIN-LOSS RECORD.  COULD I PLEASE HAVE THE NL CENTRAL COMBO MEAL?  AND COULD YOU SUPERSIZE THAT?"

(*CLEVER*  Clever, I SAY!  REEKING in CLEVEROSITY!)

(It's like a fast food restaurant for pitchers!)

If you can stomach the above line, you'll rediscover the obvious: the NL Central is bad.  Like, really bad.  Just look at the overall divisional records for Lord's sake:

NL Central :: 297-335 :: .470%
NL East :: 266-266 :: .500%
NL West :: 272-256 :: .515%

AL Central :: 271-259 .511%
AL East :: 264-265 .499%
AL West :: 217-206 .513%

It should come as no surprise that after Cole Hamels notched his 12th win Monday night in Chicago, he upped his record against NL Central teams to 7-0.  Keep in mind, he plays for the Phillies who are stationed a few miles to the right in the East.  Hamels is 7-0 in 8 starts against the Central with a 2.83 ERA.  Against all other teams: 5-5 with a 3.88 ERA.  Oh, and Hamels has yet to pitch against the worst team in the Central, the Pirates. 

Since we're investigative journalists on this here site, I did a little bit of digging and found (SURPRISE!) that 7 of the NL's leaders in wins have destroyed NL Central teams. Below are the records against Central teams compared with overall record.  You'll be able to see why AL pitchers are supposed to excel upon switching leagues.

Cole Hamels: 7-0, 2.83 ERA :: 12-5, 3.50 ERA

Brad Penny: 2-0, 2.49 ERA :: 13-2, 2.60 ERA

Jeff Francis: 5-0, 3.75 ERA :: 11-5, 4.12 ERA

Noah Lowry: 4-2, 2.99 ERA :: 12-7, 3.32 ERA

Tim Hudson: 3-0, 3.13 ERA :: 11-5, 3.09 ERA

Jake Peavy: 3-0, 1.06 ERA :: 10-5, 2.41 ERA

Aaron Harang: 6-1, 3.77 ERA :: 10-3, 3.54 ERA

All told, the combination of Hamels, Penny, Francis, Lowry, Hudson, Peavy and Harang is 30-3 against the NL Central.  All but two of them, Hudson and Harang, have lower ERA's against the division, with Hudson being a mere 4 one-hundredths of a point off his overall mark and Harang .23 points higher than his season total. 

The National League Central: excelling in suckosity.

"So, your 'investigative journalism' reveals that 7 of the top 13 pitchers in the National League pitch better against the worst division in baseball compared to all other divisions in baseball?"

"Yeah."

"Thanks, captain obvious."

"You're quite welcome."

This guy wishes Cole Hamels pitched against the Central every start.