It has never ceased to amaze me how a select few individuals in key positions in corporations are permitted to form a self-sustaining interlocked stance on the use of MS Office suite due to their inability to accept they are able learn other ways of conducting business.
MS Office has been constructed to permeate the worlds major corporations because, among other things, it offers this group an easy transition from one company to another. I suspect their main selling point in interviews is that, 'yes' they know how to use Outlook to send email and use its calendar to keep track of which meeting they are supposed to be in next.
When consulting on available options they always balk at implementation of more cost effective (read: FREE) platforms and when doing so whine, 'well the other guys all use it'. Of course as they actually voice it in terms like, 'all our business associates use it therefore we must as well'. Self-supporting hogwash. Personally, I stepped away from Office because, when testing Thunderbird ten years ago, found emails deleted in Outlook, were never actually removed from the PST file. They were simply hidden from the User.
I suspect those at the executive level, like so many others, are simply reluctant to try a new platform out of fear they won't be able to understand how to use it. Mentality akin to what makes children check under the bed for monsters. Fear.
As for Microsoft, if they lost the strangle hold they have gained through the Office Suite of applications. They very well may tumble from the lofty heights and actually have to produce a competitive product. They don't have to do so with their operating systems because of the back room deals made with PC makers by which they enforce their own rule of, 'a PC has to come with an Operating System'.
So my reply is tethered properly to this threads topic: Yes, Libre Office can be installed on an External Drive. The folks at PortableApps.com have two 'LibreOffice Portable' packages available. One for English only (120mb DL, 260-413mb installed) and one for all languages (145mb DL, 516-776mb installed). Whose features are described in part as:
LibreOffice Portable is a full-featured office suite that's compatible with Microsoft Office, Word Perfect, Lotus and other office applications. It's easy-to-use and feature-rich, performing nearly all of the functions you'd expect in an office suite, but at no cost.
They also offer support on how to copy your local LO settings to LO Portable. It requires Users find and copy: /C:\Documents and Settings\[user]\Application Data\LibreOffice\/ to the LibreOfficePortable\Data\settings\ directory. So the difficulty level requires one find the \LO\data folder on the external drive and perform a copy function.