I mean, I still think Buchholz' option had to be picked up, but let's stick to actual facts here:
Fact A) Buchholz has not combined the ability to prevent runs at an above-average clip while providing enough innings to qualify for the ERA title as stated by rule 10.22 ( since 2010. In fact, he has pitched enough innings to qualify for the ERA title only two times in the last five seasons.
2011: 82.2 IP, 124 ERA+
2012: 189.1 IP, 92 ERA+
2013: 108.1 IP, 237 ERA+
2014: 170.1 IP, 75 ERA+
2015: 113.1 IP, 131 ERA+
Fact B ) Innings pitched in a minor league setting are unimportant to the Major league club, are usually a direct result of injury and/or ineffectiveness, and trying to prove Buchholz' lack of fragility by using said statistics is, at best, misguided, and at worst, as I mentioned before, dishonest.
Fact C) Buchholz is neither durable nor effective with any sort of consistency, and even worse, has managed to combine durability with effectiveness in very few occasions throughout his career, and none of those occasions have come in the last five years, as he has gotten older and his stuff has diminished. Those are facts.