When using KeyCite on Westlaw you'll often find cases that have been cited many times.  Roe v. Wade, for example, has nearly 20,000 citing documents.  The only feasible way to deal with so many cases is to limit your KeyCite display.  When doing so, one way you can limit is by document type (i.e. cases, secondary sources, court docs, etc.).  Until now, you've always had to uncheck all the sources you did not want - an annoying process.  But, not anymore.  From Westlaw's Tom Duggan:

"KeyCite “Clear All” Now Available

 Using KeyCite Limits just got even easier! Previously, when limiting KeyCite Citing References by Document Type, you would have to individually de-select each item you wished to exclude. This became very cumbersome if there were many document types but you only wished to include a few. Now just look for the “Clear All” button at the top of the Document Type page under KeyCite Limits and quickly clear all the document type check boxes."