I try to get the youngster out in-hand once a month, so he doesn't forget how to behave at parties. I like to keep little cobs eye in, and go local SJ or a hunter trial every other month. Am currently schooling her with the view to have a go at WH with her, so hopefully be out a bit more with her this season! x
I usually go out 1/2 times per month but over christmas usually have 1 or 2 months not going out. Probably works out around a dozen times a year. Mix of DR, SJ and ODE .
I've been out 5 times so far this year but this will slow down due to other commitments at some point.
I just get paranoid if I don't keep taking him out to stuff but I think thats more an issue in my head than anything else!!
I go through periods where I try to get Bill out every week for a few weeks, then have a a bit of rest (not riding much, letting him chill etc for a week), then work on lessons with a few weeks off competing. Bill is still young (7 this year) and he's so spooky that he improves by going out often, although he's laid back horizontal at shows so they don't seem to stress him out per se - it's more the pole lying next to the dressage arena, or the dead bit of grass next to the SJ fence, that scare him so
We're only doing prelim dressage or 85-95cm SJ or sometimes an ODE, nothing particularly taxing (bearing in mind we are rarely placed SJ/XC and are extremely slow). He had 6 months off competing over winter (mainly due to an injury). Had he not had the injury, the plan was to give him Jan and possibly Feb off to chill out.
I don't think you should worry about taking your horse out too little - only taking it out too much! (I worry I take Bill out too much).