The automaker's ace in the hole might not be anything design-related, however.  Rather, it could be production: McCarthy notes that Tesla faces a "challenge" in making so many cars on time and within budget.  That shouldn't be a problem for an industry veteran like Mercedes, he argues.  And while he's unsure that the car is built to be a "Tesla killer," he admits that Elon Musk and crew will "probably have good reason" to worry about it. 

In that sense, Tesla may be shifting focus to the more affordable Model 3 at just the right time.  Although Mercedes (or rather, Daimler) technically has low-cost electric cars like the Smart Fortwo Electric, they're not exactly mainstream.  Tesla will be targeting an audience that Mercedes has largely left untapped, so it won't have to worry all that much if its higher-end car sales take a hit.