data item uniqueness

[roger]

Working with a CDM I observe that every time
I add an attribute to an entity, a new
"data item" is created.

Problem is, if I add an identically named attribute
to a second entity, what seems to happen is that PD
automatically links the new attribute to the same data item
that was created previously.

Then, if I rename one of the attributes in either of
the two entities that contain it, I see that the name
changes in all entities that use that attribute.

I'm sure that's a good thing in some cases - like if I
had explicitly specified that the two were linked.

But this is rediculous. Is PD telling me that you
aren't supposed to be able to reuse any attribute names
anyplace across an entire model?
That I can't have EntityA.Name and EntityB.Name
as distinct data items or whatever?

I'm supposed to instead create a distinct things like
EntityA.EntityAName and EntityB.EntityBName?

That can't be right.

Can it?

Please tell me I'm missing something obvious here...

roger