Multiselecting Dates in Excel 2013 on top of SSAS/BISM Multidimensional

It is not uncommon to compare BI clients on a very detailed feature level in discussions with customers but this blog post is about a question in the Analysis services forum that I posted an answer to. I have written a longer blog post on the SolidQ blog about the most important new features in Excel 2013 for multidimensional analysis and this post add a feature that was not on my mind while I wrote this: