Hierarchy by User

I am building a site for my scout troop, using drupal 6. What I'd like to do is have content divided by patrol (groups within the troop). I'd like patrol members to be able to add and edit content in their own "section", but not be able to edit or add content to other patrols' sections. I suppose the simplest (from a drupal perspective) would be to define a content type for each patrol, and for each "real" type, but that makes a huge amount of administrative overhead. In addition, the names, and even the number of patrols changes from year to year.

I guess what I'd like to do is arrange the content by taxonomy, but restrict the terms that could be used by patrol. Is there something like this? I see "user_force_term" but only for drupal 5.

1. Is this the correct way to be thinking about this problem, or is there a better way to do what I want? What do other drupal sites do for similar situations?

2. Is taxonomy the correct tool? Are categories more appropriate? The module description for categories scared me.

Thanks for the advice!