At $WORK we use Mozilla Rhino for some JavaScript processing.
We tested the normal loop vs. the clever loop. Performance-wise, the normal loop blew the doors off the clever loop.
We tested the normal loop vs. the clever loop. Performance-wise, the normal loop blew the doors off the clever loop.
When it comes to performance, lessons that apply to Rhino are unlikely to apply to more mainstream engines.
EDIT: That's not to say that everyone should use map and forEach all the time, just that your benchmarks are unlikely to be relevant to most JS devs outside of your specific use-case.