Why would 1 thread be quicker?
Quicker than what? Both times are for 1 thread. The only difference is that your first example sets itself up some overhead by pretending it's going to use multiple threads and then doesn't do it.
Quicker than what? Both times are for 1 thread. The only difference is that your first example sets itself up some overhead by pretending it's going to use multiple threads and then doesn't do it.