I often have been asked this question in A&R-Trainings: Wouldn't it be possible to keep the colour used be the System to distinguish between dimensional values in a Portfolio Object if the selection is limited to one of those values, only?
Example from the Training: The sales persons can be distinguished in the chart if more than one sales person is selected (eg. sales person A is shown in green, B in blue). The idea would be to keep this colour-coding even if the selection is limited to one sales person (eg. sales person A will stay green) - unfortunately, this is not the case.