Using annotation codes to format text

Im trying to produce subscript using sprintf statement. I've attached 2 pics of code and the result. Can someone tell me why its works in pic 1 and not in pic 2. I think that it has to do with annotation codes working in one instance and not the other but I don't know why. I've spent hours on forums and in the manual and to be honest im frustrated. Thanks for any help or insight you can provide. SubScript1.jpg SubScript2.jpg
My guess is that Notebook text does not follow the same formatting rules as annotations and controls.
This is indicated by the following part of Notebook command help:
vOffset=v   Sets the vertical offset in points (positive offset is down, negative is up).
Use this to create subscripts and superscripts.
vOffset is allowed for formatted text files only, not for plain text files.
In a notebook, manually format the text as you wish. Then use Notebook->Generate Cmds to copy the commands needed to generate that text to the clipboard. For details, execute:
DisplayHelpTopic "Generate Notebook Commands Dialog"


For details on formatting text in notebooks, execute:
DisplayHelpTopic "Notebook"

and scroll down to "Notebook text property parameters".