Too bad, the mountain bike community is too weak and unorganised to make this kids able to build legal trails. Unfortunately, even if in a short term it's sweet to have new trails, this kind of trail creation on a private property and without any ecological considerationwon't help to promote freeriding in the SD area. BTW the secret spot attitude is just completely stupid, maybe it can help you to keep your spot one more month but you're sure it's going to be wiped out at some point. The only successfull way to keep a trail system for a long term is buil legally with the community agreement. An article about the legal opportunuty to build trails at the future SDMBA skill park at Mission trails or at Vail Lake. As an example, watch what happened to the "secret trails" at Flightline and how new trails can be build and preserved at La costa when builders work with the different organisations and agencies... I'm not (yet) member of the SDMBA but I thing you guys would better try to be massively involved in a local organustion to work together instead of wating your time on internet (like me)