I generally buy my software, so if I buy this I'll be stuck with (yet another) fractious, draconian and probably brain damaged DRM mechanism, whilst those who pirate it will inevitably have the cracked version without any of those annoyances.
In the pre-internet days that cracked version would be hard to find, but now anyone can find warez in a matter of seconds by using any internet search engine.
By adding DRM I can guarantee you're losing at least three sales in this extended household. You may be thinking that's an insignificant speck of users, and you're right, but when many others make the same decision the numbers can quickly mount up.
So, by adding DRM what you're actually doing is adding a significant disincentive to purchase the software. DRM is not only customer hostile, but it's >sales< hostile too.
Many other people ask me for my input as part of their buying decision, and if this comes to pass I'll be steering them away from MSoffice.
The only people you ever stop with DRM protection are a few simple minded home users, most of whom would never buy the software anyway IMO; which means they're a non-market to begin with.
All of this would be irrelevant if MSoffice were the only option, but OpenOffice is free of copy protection, as well as cost, so I'll go there instead. Sure, it doesn't do a few of the useful things from MSoffice, but it does everything I need it to without the DRM.