Perhaps there’s a measure of defiance in the title of Merle Haggard’s 2010 album I Am What I Am, but it’s also a statement of plain fact: almost 50 years into a recording career, there’s no changing the fact that Hag is who is he is, and he’s comfortable in his own skin, broken-in but not worn-out, never pushing too hard but never coasting, either. Sometimes Haggard’s easy touch is too light, slipping into sleepiness, but the striking thing about I Am What I Am is its casual mastery, the subtle shading in his vocal phrasing can make his songwriting appear effortless.