Miles and Miles

How many innings on a relief pitcher is too many? No one knows for sure but Scott Proctor has more out of the bullpen than any other pitcher this year. The Yankee reliever was back in there tonight in the 8th with a 4-1 lead despite the division being wrapped on Weds. night. Might it be time for some rest at this juncture with a full load of hurlers in the pen? More than a few detractors point to the perceived mileage and subsequent breakdown (in spectacular fashion) of Paul Quantrill a few years back. It may be an unfair comparison as Q had a history of arm trouble prior to the extra long work the Yanks asked of him but I wonder if caution might be a better approach at this point. Any thoughts?