Sources close to Microsoft claim that the version of Office 2013 that ships for Redmond's Surface tablet and other ARM systems will be missing features from the build for rival Intel-based Windows machines.
Among the items to be pruned from the version of Office for ARM-based Windows RT will be macros, third-party add-ons, and support for Visual Basic for Applications (VBA), The Verge reports.
The features are allegedly being removed to conserve battery life and improve reliability on devices with limited processing power.
If true, it would be something of an about-face for the software giant. At a press event announcing the Office 2013 Preview in July, Microsoft honcho Steve Ballmer said that Redmond was committed to providing the full Office experience on Surface and other devices running Windows RT.
"You'll see this as we and our partners ship PCs and Surface devices with ARM chips in them," Ballmer said. "Full Word. Full PowerPoint. Full Excel. You give up nothing of the rich capabilities of Microsoft Office when you embrace a Windows 8 ARM device."
Microsoft only shared a glimpse of Office running on an ARM device at the launch event, though, and the preview version of the suite did not include the promised don't-call-it-Metro-style versions of the applications.
If the reports are true, "the rich capabilities of Microsoft Office" on ARM will not include any of the tools that businesses use to develop custom forms, templates, and applications based on the productivity suite.
It wouldn't be the first time Redmond has disappointed users this way. When Microsoft discontinued VBA support for the Mac OS X version of Office 2008, it ultimately was forced to extend the support period for Mac Office 2004 until 2012 to appease Mac fans who relied on the scripting tool.
Microsoft has previously said that ARM-based Windows 8 devices, including Surface, will ship with Office Home and Student 2013 RT, which will contain "new versions of Word, Excel, PowerPoint and OneNote applications."
But here Redmond is certainly saying less than it knows, and perhaps more than it seems to be. For starters, there is nothing in this statement to indicate that these new versions of the Office applications will be identical to the ones that ship for Intel-based Windows.
Furthermore, even if Microsoft does make available a full version of Office for ARM, as Ballmer has promised, there is no reason to assume that this is the version that will ship with Surface in October. If that version is indeed a preview release, as reports suggest, then it may well be hobbled in some ways, and the full version might be a for-pay product to come later.
When asked for clarification, Microsoft's Office team told El Reg, somewhat cryptically, "We have not finalized packaging for the next release of Office." ®