Most outdoor companies use fit models to help design their standard products, from which all different sizing options are created based on a grading scale. Some companies, such as The North Face, have experimented with user controlled software that matches your personal measurements to the best corresponding product size. Petzl is taking a more proactive approach by reaching out directly to you, asking you to send in your body measurements to help the company better design future product sizes.
You know the feeling-you have taken the occasional rock or ice chunk to the head or had a couple of nasty falls on your mountain bike but don't want to get a new helmet without knowing for sure the old one is toast. Well now you will be able to know for certain if it is necessary to replace your helmet with a new process that causes stinky oils to seep out of plastic materials when they are damaged.