Car suspension tuning is a very subtle and difficult black art. It's all about what's happening dynamically in response to transient inputs (go around a corner, hit a bump, etc.).

I believe Lotus does a lot of engineering consulting helping other manufacturers dial in suspensions. I wouldn't be surprised if Tesla had them consult.

Even some of the big car companies have trouble dialing in suspension on their own (I'm looking at you underdamped Japanese cars). European brands tend to be really good at this, and can take the same raw materials that everyone else is working with and create superior setups. Porsche somehow manages to start with the 911 where they stick the engine way out behind the rear axle (high polar moment of inertia, poor front/rear weight distribution) and make it handle beautifully. VW cars also tend to have great suspension tuning. Being able to keep the weight low to the ground in the Tesla contributes to a low center of gravity and I imagine must really help enormously.

Also the body under-tray is beautiful, like something you'd expect to see on a purpose built race car, probably helps a lot with the aerodynamics. I imagine more and more cars will get similar under-trays to improve aerodynamics and fuel efficiency.

It's interesting there is strong anti-dive geometry built into the car, probably to avoid problems with throttle lift oversteer caused by inexperienced drivers. I wonder if the current Model S handling leaves anything to be desired when driven to it's absolute limits and how the car would handle with some of the anti-dive geometry removed. Removing this geometry is a common mod on some cars.