So far, this IS who he is, Jeckel and Hyde .... With Max Scherzer as his partner, these two swapping positions time to time.
So far in Porcello's career he's been given a pass, he's not the Top pitcher, so the pressure isn't on him.
The excuse has been "He's Young", he did start very early, Tigers rushed him up back when they had no one else to go to.
He IS young, just 23, seems like he's been in the rotation forever, however this is his 4th year, seems like you should have consistency of some sort by now.
So, as you said, maybe THIS is who he is, always to be inconsistent and baffling.
Was reading a article in the paper this morning on his performance yesterday, forgot he's is 23 as well. He was brought up pretty early in his career