Yes the performance of each reliever seems to vary from year to year. There was a guy about 20 years ago, Cliff Politte, that I remember thinking at the time that he was pretty steady and dependable, and could be used for multiple innings. Looking back at the numbers now though, he had a couple of nice years but they weren't consecutive, and in many years his IP was less than his G. I think the last guy that the Tigers had who could put out a fire in the 7th inning, consistently, was Shane Greene. It was a role that suited him better thsn closer I think.