Since the first version of TFS Microsoft provides plug-ins for integration to Excel and to Project (and, since the 2010 version, also for PowerPoint) that simplify the access of non-technical personnel to the project.
Of course, this was a "price": these people needed to install the Team Explorer (in practice, a "light" version of Visual Studio) on their computers. A tremendous overkill for just need to connect your Excel to TFS.
That just changed.
As Brian Harry announced in a recent post, from now on, the plug-ins from Excel, PowerPoint and Project were disassociated from Team Explorer and will be offered on a stand-alone download: Team Foundation Server Office Integration Installer. For while still in preview (the final version should come out along with the final versions of TFS and VS 2015 Update 1), the new installer is tiny (compared to the "big" Team Explorer) and, above all, does not create an icon of Visual Studio that often confuses users and to the Auditors of large enterprise software licenses who are led to believe that there are more licenses of Visual Studio in use at the company than it really is true.
Ah, another good news: If you haven't noticed in the above paragraph, I mentioned also the PowerPoint. That's because the functionality of storyboarding ("scripting interfaces") of Visual Studio (based on PowerPoint) is also included in this installer. That is, no longer need to install Visual Studio (Premium, Ultimate or Enterprise) to have access to the resources of storyboarding. Alive!