some client have standard.....
one of these want only SIMPLEX style in drawings..in 5 specific layers, all block created to layer "0" etc....
but we receive some drawing from architect and diffrent other discipline who work with there standard.
so when we receive these drawing we always need to clean all textstyle and fonts before returning the drawing to the client.
To obtain in the drawing this final result of textstyle:
Standard and SIMPLEX
I understand what you want to do and why. I'm just suggesting you don't need code because CAD Standards can do it. And it would do a better job than what Tim posted. As he said, "It won't change the text (style) for dim styles, or for formated mtext."
CAD Standards would get rid of any unwanted text styles contained in dimstyles. And it purges unwanted items, those which were replaced, in the process.
Regarding Tim's comment about formatted mtext, that is, or should be, a concern. If an mtext string looks like this, "{\\Fromans|c0;SEE ROOF PLAN}" it will display using ROMANS regardless of what the style name property is. To fix that there's John Uhden's Unformat function. It allows removal of font formatting in mtext without changing other formatting codes which you'd probably want to keep.
Tim,
If you read this, I trust you know it's not meant as criticism. Basically I'm just underlining what you said.