Speed: Another Reason to "Trim" Calendar Tables

I've been doing some work lately for a client who really pushes the DAX envelope. One of the top-three models I've ever worked on in terms of complexity, no doubt. And really, my role is just to help fine-tune it and add a few bells and whistles. They built this sucker themselves and I am way impressed. Crazy stuff. Formulas that use outlier dates from one Data table ("fact" table) to then subsequently filter another Data table (via its related Calendar table), but then wrap that up inside a MAXX inside a SUMX. and it all makes perfect business sense. It's magic.