I work on the Power BI CAT team at Microsoft and spend my days tuning very large and complex Analysis Services data models. I learn plenty as I go, and use this website to share what I can. All statements across the DAX.TIPS website are 100% independent from my employer (Microsoft).
If you would like to learn more about DAX, my book Beginning DAX for Power BI is available on Amazon.
Twitter : @PhilSeamark