I had planned to have my guitars done each year but now I'm not so sure. My luthier is well known/widely respected in the region and he said such frequency wasn't necessary.

Now...that might be due to the guitars themselves or my style of playing or the amount of time I put in on the guitars. They're all high quality instruments and the three I currently have get a combined total of about 70 hours/month play time. They aren't played 'hard', they're wiped down after every play and get a more thorough cleaning weekly.

So, since they sound nice, play nice and don't seem to have any intonation issues and my luthier says 'don't bother' I guess I'll save the money and the time...