[slrz]

The difference is more apparent in the other (non-overloaded) case. When in Go (or C, …) you see an expression "x << y" you know immediately that this is just a shift operation, mapping to at most a couple machine instructions. In certain other languages it's most likely an integer shift, too. Still, you have to carefully consider the context lest this simple shift expression causes synchronous I/O to some space probe near Mars