I think that putting an expiration date on a cert might be a good thing so that re-training is required after a period of time. It's required for CPR so why not something as important as climbing or rescue? What is troubling is that companies are deciding what that retraining period should be. Sort of like the fox guarding the hen house. In a couple of years I could see them calling for recertification every year. If I owned Comtrain I surely would.