[alanctgardner3]

Two things stick out:

Catching unused variables is pretty essential, it's easy to shoot yourself in the foot by redeclaring a variable with := inside a block.

>> which means you have to need separate storage for the actual RaceCar and GetawayCar values, either on the stack with a temporary variable or on the heap with calls to new

Maybe I miss his point here, but in Go it's totally valid to just create a new *GetawayCar with &GetawayCar{} in any scope. You can return that pointer from your current method. It's not necessary to explicitly put your GetawayCar on the heap with new(), Go will decide for you with escape analysis.