Why shape Text is not available as a ShapeSheet cell?

[Nikolay]

Why shape text is not a ShapeSheet cell (or was not made available as a shape-sheet cell)?

I mean, you can access shape text using SS formulas and use SS fields in shape text and so on, but still you can't set the text directly from a SS formula for example.
Why? Is there a reason for that?

Just curious, i.e. the question is well about Visio design in general, not a practical one.

[Yacine]

Guess because shapesheet cells don't support formated text

[Nikolay]

But isn't "Shape.Text" also plain text, and formatting is added afterwards by other SS cells?

I.e. the question is, why the text, that is, "Shape.Text" (in VBA notation) is not a SS cell (or was not made available as such)..

[wabright]

Its due to the formatting of the text.  Evaltext and shapetext formulas should get you what you need. 

http://www.visguy.com/2009/03/10/evaluate-shape-text-with-evaltext/

https://msdn.microsoft.com/en-us/library/office/ff767248.aspx

[Nikolay]

Actually, I don't need anything in particular, just curious

The article states that:

While there are good reasons for this, I think this can initially trip-up would-be SmartShape designers.

The reason there is no text cell is because text can have different formatting characteristics. Bold, italic, underline, strike-through, bullets, font size, etc. Paragraphs can have different alignment. Some text might be typed by the user, other bits of text might be linked to inserted fields. In short, a shape's text can be an unpredictable mish-mash. In light of all of this text-complexity, simply asking Microsoft for a Text cell might be a rather unclear feature request.

So my question basically is, what are these good reasons?   
Text formatting does not sound like a reason to me (or I don't quite get the relationship between formatting and absence of text in the ShapeSheet) - again, "Shape.Text" has no formatting.
As for the fields, the text just has those &H1E characters for the fields.