[Christian]

GTD is just a rough idea I think. It has to be applied to your personal needs.

I do not go by what GTD says, in a strict sense. For example, for work I have a category because I have several multi-task projects in it as well as a single action list for single tasks. For other areas like sports I just use a single list. Many steps you have to actually undertake in order to get to a desired result are self explanatory, logical and indispensable. If I want to buy new running shoe I know I have to drive to the store, yell at the staff to show me the newest models, test them, pay them, drive back home. Do I need a single action for those logical, indispensable steps? No.