Row Hiding in a Matrix

Hi,
I have a P&L report that I am trying to produce. Due to the many
column groups, I prefer to use the matrix method.
However, I can't seem to surpress duplicate rows that are created
because in some instances the total value of the outer row group is the
same as the total value of the inner group.
I was performing this nicely with a table by using the visibility
surpression on the entire row (which didn't get rid of the outer
group).
It seems there is no equivalence in the matrix control and when I set
the visibility of the outer group to conditionally hide none of the
inner group values seem to show (I guess this is by design)
I guess what I want to do is to surpress the visibiliy of either the
summary or the last inner group.
When I try to conditionally set the visibility of the summary, the
label is not shown but the total value is.
Either method seems to have a limitation.
Any ideas?
ThanksI tried Hide Duplicates, too, but that doesn't do anything even though
the visible fields of the two consecutive rows have identical values.