Does no one remember Jake Peavy? Following the added workload of the WBC, Peavy's ERA went up by 42%, his walks went up by 25% and his home run rate increased by 28%. He went from being 34% above league average in terms of his ERA to 1% below.
Looking deeper into the stats, we find that Peavy's BABIP was a bit high (.316), which clearly accounted for the 15% increase in hits between 2005 and 2006, while his HR/FB rate remained constant. However, this all happened to coincide with Peavy's 6% decline in groundballs and 8.1% increase in FB's, which led to an increased homerun rate and FIP increased of 21%.
All and all, it seems like Peavy's number were probably affected by some combination of luck and/or fatigue. While Peavy's most of peripherals remained relatively constant, his control was clearly affected by some measure -- and walks tend to be relatively luck neutral. Thus, I am tempted to side with the latter explanation (fatigue).
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EDIT: Now the roundtable is talking about the youth movement in baseball. Never one to say something intelligent, Steve Phillips -- again in his opinion as "an ex-GM" -- is advocating drafting High School players over College players, despite all statistical evidence that points otherwise, because you can get "younger players."
Side note -- Phillips was notorious for signing aged veterans -- like Mo Vaugh, Bobby Bonilla and Kenny Rogers -- to expensive contracts during his brief tenure as the Mets GM.
Ay yi yi.