A new rev of Outlook is out. I used the auto-update option and always just update the environment when something new is available.
This time it is Outlook Version 15.18. It has couple of new features and the performance of Outlook on my OS X El Capitan Macbook Air is horrendous once again. This is a recurring issue.
They will probably find a fix within few weeks and push another update. It happened before. But for now, Outlook on OS X is almost unusable. Every preview of email takes for ages and you see the OSX Spinning Wait Cursor. You want to open an appointment on the calendar. Same thing happens. It takes time.
Continue to be a disappointing experience to the point i am considering to stop updating Outlook automatically and switch to a once in a year update