Sorry, but most folks who use a Mac at work most certainly use Outlook as well. The fact that El Capitan breaks Outlook is a deal-breaker for me and just shows how bad Apple's QA is. Outlook is one of the most important business apps and Apple releases an incompatible OS upgrade? Really? How can that happen? (That was rhetorical - Apple breaks compatibility with every new OS X upgrade; by now everybody knows that they don't give a damn.)
Office users will have to postpone the El Capitan upgrade until either Microsoft or Apple provide a fix for that problem.
That was my worry. I’ve installed Office 2016. I’ll see how that fares.
Looks like I have to pass on El Capitan as Office 2011 is a must for my work. UGH!!!