There are 2 things they should be doing. there is some service information regarding misfire codes. Along with the valve adjustment they should be doing a PCM(engine computer) reprogramming. It is not that abnormal if Honda does have some service information for the technicians on this. from my experience with Hondas, the valves usually tighten with age and you will never know because they will not get noisy.
Thank you for the information Steve. I just needed to bounce this problem off some one
other than the dealership.