Generally, if you need to script text format changes to OmniGraffle, it is probably quite important that you are aware of a pair of 'model lag' bugs, a Scylla and a Charybdis, which can either mean that the screen is misrepresenting the state which your data will be in when you save it, or can mean that the Applescript interface will be misrepresenting that state.

It turns out that the OmniGraffle screen can even deceive us as to the contents of the text in our documents ...

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