I don't see presence patrolling and task/purpose to be mutually exclusive.

I gave patrols the task and purpose of gathering a list of PIRs/IRs in a given area, disseminating messages to specific TA's, and, yes, even the much-hated "route clearance." However, these patrols were intended as "presence patrols." If they came back 4 hours later having none of the IRs answered, I still felt the mission was a success if they sustained a lengthy presence in a specific area, put out the messages, and conducted themselves in a manner that reinforced the messages. If nothing else, they were staying familiar with the lay of the land. That familiarity alone was invaluable. Most of the IEDs that we identified were spotted by a Private who noticed that, "something over there looks different." Plus, whenever a platoon of my guys showed up in a locale and showed their intent to stick around for an extended period, the locals would open up their fruit/vegetable/other stands because they felt safe. Very good for earning their trust and cooperation.

It worked even better if a few team-sized OPs were inserted into overwatch positions near the neighborhood during the prior night. Many foolish d-bags felt the sting of a 72-grain bullet in the back while moving into an assault position in an ill-fated attempt to shoot at the stationary American patrol, not realizing that an 18-year-old American was watching him and impatiently waiting for his team leader to give him permission to deliver the news.