Strange Perspectives

In SSAS Persepctives are a very useful tool to control the visibility of objects (dimesions, measures, hierarchies etc.). They represent subsets of cubes and define Views with the relevant data for a specific audience. In the Perspectives tab of the cube designer in BIDS I can exclude objects, that I want to hide from my users. But obviously sometimes SSAS does not believe that I know what I do:

In the following example I defined a simple cube with only one measure group and some dimensions. In addition I created a calculation TestQuantity. In the Perspectives tab I choosed to include all the measures and the additional calculation:

In the browser we see the expected elements:

Now I exclude some of my measures from the Perspective:

And again I get the expected selection:

But when I exclude all the basic measures and want to include only my calculation, SSAS apparently starts to question my accountability:

The result again contains all the measures of the group, I wanted to exclude:

Perhaps SSAS believes that a cube (or a cube view) without measures is not very beneficial, but since the calculation TestQuantity was not excluded, I see no reason for this implicit addition of objects.

For the sake of completeness a link to William Pearson's article on Perspectives in the Database Journal and another one to the (books online) documentation.