Don't forget that he's in wildfire prone San Diego. We've had "hunters" start signal fires that literally burned down the county ( Cedar Fire). While fire-making skills are a good thing, in San Diego staying warm without fire is a good preparation goal.

I have no plans to go off road into a gully. I drive with the intent of staying in control and on the road. That said, it's always good to have a "Plan B".

I look at the vehicle as primary emergency shelter; however, I keep an Alpine Bivy and a lightweight sleeping bag in the car for shelter outside the vehicle. There's also a winter kit (wool underwear, synthetic outerwear to include parka) in the bed if I get stuck in the Siskiyou's on I-5 (NOCAL, Southern OR).