yes it is, i just double checked it.
maybe it has to do with the fact that i am formatting the dynamic date of the chb even though i dont need the actual date written anywhere.
i did try
member [Measures].[VOID] As
(strToMember("[CHB Date].[Year - Month - Period - Date].[Date].&"), [Chargebacks].[CHB_Tree].[CHB Type].&[IRS VOID], [Measures].[Purchase - converted to USD])
without the format, but i also get an error.