Could you elaborate a little bit more on the last sentence in your email: "IIRC it works this way in Office 2007
"? There is no part of the MS specification that addresses this aspect of the key tips. Other than that, in terms of the user experience, enumerating hundreds of options with numbers is not optimal.
You are 100% correct about the resolution of the enumerating scheme you've mentioned, but still - it will add additional burden to the way users interact with the ribbon. Just imagine having a lot of options and instead of entering "1" or "01" you have to enter "0001".
Contact me again if you need further assistance.
the Telerik team