I was able to re-create this same behavior in the "Customizing the QAT" sample with the "Italic" command. I added the Italic command to the QAT via the list boxes at the bottom of the sample. Applied the changes the Italic command was then in the QAT. Then I went to the CanCloneToQuickAccessToolBar ribbon and added the Italic command to the QAt and ended up with duplicate Italic commands in the QAT.
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