Carbon cover really does work well to protect case, but only once!
In crash, fairing gets squeezed between ground and side case. It takes maybe 3-5ft of sliding to grind through fairing and remaining 100ft is on engine case itself.
AFM have always required stronger aftermarket cases or case covers on certain models known to have "glass jaw" cases that crack or grind through easily; i.e. all GSX-R, R1, R6 left side, etc. Seems they got tired of maintaining list, identifying these models, and checking at tech, so they are requiring case guards on ALL bikes this season.
Might also be overreaction to numerous aftermarket oil-filter failures last year. There was 5-bike pile-up at Thunderhill last year where one guy broke both wrists, an RSV4 sustained $7k in damage, one helicopter and two ambulance rides, etc.
Since no metal case guards are available and
used factory engine cases are cheap and plentiful, I'm just going to use a factory case and double them up. Chop off the top-half and sides. Bevel/grind inside so it spoons over the case easily for two bolt-holes to line up. Then epoxy and/or weld it on.