Wilson Po clued me in on this technique right after I started working at Tableau. Loved it then, love it now for its simplicity and utility. For reasons unknown it popped into my head just now, so let’s do a little blogging – it’s been a while.
Anyway, this approach allows you to “hide” a dimension value rather than “filter” it out of the viz. Very, very useful when you’re working with averages and don’t want to see something, but at the same time don’t want to filter it out lest your total average change.
Use this sucker in a quick filter and you’ll be able to hide whatever members you want without actually removing them from the set of data being operated against.