Re: Mike Leake may be running on fumes...
Bronson Arroyo doesn't have any superhuman skills. He has no special sauce. He is governed by the same laws of physics that control other beings in the universe. ERA, FIP, xFIP and SIERA apply to Bronson Arroyo just as much as they apply to all other pitchers. The notion that Arroyo's "veteran savvy" has allowed him to outperform his peripherals doesn't hold any water when you take an objective look at the full picture.
Take a look at his stats below and see if anything stands out as unusual or unexpected:
Bronson Arroyo's Statistics Since Joining Reds in 2006:
260 Games Started
1660.1 Innings Pitched
I don't see anything out of the ordinary there given the fact the Reds have had a better than average defense during most of his tenure, which would lead us to expect he would slightly outperform his peripherals, and he has. He has outperformed his peripherals by approximately the same range as most Reds pitchers have. Cueto, Ondrusek and Cordero outperformed their peripherals much better over the same period, while Volquez and Harang underperformed their peripherals.
Arroyo has been a league average starting pitcher throughout his Reds career. Like any pitcher he has seen his ERA swing up and down based on fluctuations in his BABIP and LOB%. When all is said and done it doesn't appear that Arroyo has any special savvy or ability to get better results than his peripherals would predict. If anybody does it is Johnny Cueto, probably due in large part to his ability to pick off runners and control the running game.