First, I'm not sure what to make of having two backs with 3 concussions and at least 15-16 missed games last year.
But if you're wondering whether Westbrook would be okay after missing training camps -- it'd probably be okay given McNabb knows him better than anyone. Last year he only started practicing August 16 (albeit with Philly playbook, etc).
Vick, Westbrook on practice field at Eagles training camp - USATODAY.com