I recently added an informal dirt trail that links the Guadlupe River Trail to Component Drive and the Karina VTA light rail station. this short-cut through an open field shaves nearly a mile off the current official route that goes all the way to Trimble.

Thanks to adbrown who pointed out that this trail is actually the proposed future Component Trail: http://www.sjparks.org/Trails/ComponentTrail.htm

It is noteworthy that the current path as it exists has a very steep slope at the junction with the Guadalupe River Trail, but I'm not sure how to tag this.