Seems that it should be a two-level interlock, as is found on some high-end sportscars. The regular key allows for regular driving, but the Valet Key limits it

Seems that it should be a two-level interlock, as is found on some high-end sportscars. The regular key allows for regular driving, but the Valet Key limits it to just over walking speed -- obviously sufficient to park & retrieve, but no good for joyriding. I'm quite surprised that this was overlooked in post-9/11 security reviews.