Debugger does not debug through Calculation Group / Item Logic

It appears that the debugger does incorporate the logic contained within a Calculation Item, however, the debugger doesn't step through the DAX code within the Calculation Item. I added a Calculation Group and Calculation Item with the following code to an Adventure Works DB and the debugger calculated the correct results, but code within the Calculation Item wasn't stepped through. VAR M = SELECTEDMEASURE( ) RETURN IF( M <> BLANK( ), M * 2 ) I didn't see this posted as a limitation in the DAX debugger documentation.