> if `fib(42)` is the topmost node of your program's normal form, you always want to parallelize its branches (`fib(41)` and `fib(40)`) How does that make thin

> if `fib(42)` is the topmost node of your program's normal form, you always want to parallelize its branches (`fib(41)` and `fib(40)`) How does that make things more efficient? Naively, it seems like the fib(40) and fib(41) threads are going to do almost exactly the same computation, assuming they're also defined recursively.