I just discovered something I love using this big 'ole brush for! I'm doing a series of value study exercises and got inspired to try using white and two shades of graphite pencil on a light grey toned paper. It's something I read about in Andrew Loomis' book Creative Illustration
Instead of buying a toned paper I mixed up a really watery wash with black gouache to lay down in my sketchbook. This brush was wonderful for that purpose! My other largest flat brush is a 1/2" flat and it would have been kind of a pain to use on the 7x10 paper. But this one was awesome.
Granted, I wasn't going for a lot of control or anything, but now I want to tone a bunch of pages with it
(post to more about the process I'm using for these quick value exercises)