It is pretty uncalled for to claim zealotry when you are uncompromisingly demanding an absolute 100% accuracy with MS-Office documents before LibreOffice could be used.
There are plenty of businesses where pixel perfect accuracy is not required when sending documents outside the company. If people really need to read my documents with absolute accuracy, then I can PDF it. If I want to test a slideshow then I can use the Powerpoint viewer (it even works under Linux using Wine).
Even without changing the version of Word, a document's pagination can vary wildly depending on the printer driver being used. You don't even change your software for Word to go wrong.
Excel can be a problem if you use complex macros, but 99% of the ones that I see are just being used a glorified table editors with basic calculations. I constantly move between different computers, using Excel, Calc and even the shareware spreadsheet Spread32 (when I want to view something quickly) and it all works better than I had expected. The bigger problem that I have is when a package doesn't implement a feature that you are used to. For example, if I want to search for something spanning the sheets of a workbook I will always use Excel because LibreOffice disables the "Find All" button when you choose the option to span worksheets.
But even you there may end up being some problems, you should not dismiss the use of LibreOffice within any business environment just because you might have some formatting problem.