Most of the time, when I read my email I don't think of myself as being in "processing" mode. I just answer the emails as I come to them (most of the time). If I'm in a hurry or if I decide not to answer an email right then I guess I step into processing mode.
Originally Posted by kelstarrising
Limiting yourself to doing only things that take less than 2 minutes means you're in processing mode. Just reading and answering a bunch of emails more-or-less regardless of length means you're in work-as-it-turns-up mode.