There is a tool to use to smooth mats. It helps to heal some of the wounds! Yes, mats can wear out. There are self healing mats, some rather pricey. A good mat is a good investment! :lol:
I cut in different areas so as not to wear a groove. But pushing too hard might be a problem. Elsewhere on this board there is a thread about using the tool to sharpen your blades :lol:
I have had my mats for several years and they warp if not stored properly, and I have had that problem. :?