David recommends to divide the process, i.e. Collection and Processing. Does it mean that when I have a "stuff" coming on me I just put it into "In" for later Processing? If so let's imagine my boss passes by and delegates me to do something. I write this into my PDA as a NA into some of the @Categories. Is it correct or I should put it into the PDA without category (using for example NO category as an Inbox for all new Stuff) and Process it later with other things in the Inbox during my Inboxes Processing time in the evening?