Behavior of VisualTotals

If VisualTotals is used in definition of a query named set but the set itself is not projected on any axis, should VisualTotals have any effect on query result? If the following is run against Adventure Works cube it produces differnet results depending on whether [Date].[Calendar Quarter of Year].[All] is passed or not to VisualTotals:

with
set XSet1 as VisualTotals({[Date].[Calendar Quarter of Year].[All],[Date].[Calendar Quarter of Year].&[CY Q1],[Date].[Calendar Quarter of Year].&[CY Q2]})
select [Measures].[Sales Amount] on columns,
non empty crossjoin([Department].[Departments].[Department Level 01].members, [Date].[Calendar Year].members) on rows
from [Adventure Works];

I haven't found any desctiption of what the correct behavior should be. Hope someone has more info.

Best Regards,
Alex