Horizons of Focus 20k +

I received the GTD template cards and have already created a project to go through the "Incompletion Trigger List", which looks like it'll really help me. I also want to record my horizons. I have a general list of goals, but have honestly never broken it down into these steps. I look forward to that as well.

My question pertains to how frequently should one look at the Horizons of Focus 20,000 and above? By "look", I actually mean read it as opposed to reviewing and revising, since that timeline is suggested on the template. Do you read it daily? Do you read it during your weekly review?

Responding specifically about the 20K areas of focus -- I review those weekly. I've found that to be a great way to relieve stress. For example, if I have a gnawing sense of anxiety, reviewing my 20K areas of focus will often clarify the underlying issue. That can work either of two ways. Maybe I am not giving enough attention to an area that is clearly my responsibility. Or maybe I am giving attention to an area that is not my responsibility. Once I have identified it, I can then communicate with my family, coworkers, neighbors, etc. about my commitments. Objectifying my 20K areas of focus is another angle on the mind sweep for emptying my head.

I have them posted in fairly large letters on my studio wall, so I look at them several times a week.