The easiest way is to consider if the text should be static, while you are adding a new dimension to your drawing.
Steps:
Chose e.g. linear dimension from the toolbar
Press enter
Select the line you want to be dimensioned
send the command “Text” ( or just “T”) and press enter
Write the dimension you want, press enter and end up with
positioning of your new dimensionline.
If you already has dimensioned an object, then use “Dimension Edit” from the toolbar.
Send the command “New” (or just “N”)
The “Multiline editor” will appear and you can change the
dimension.
End up by selecting the dimensionline that you want to
change.
Afterwards you can stretch objects by the command "s", without affecting your dimensiontexts
Regards from KBBJ