[throwaway2016a]

Just the other day I showed one of our junior devs how they could turn their 10 lines of somewhat slow and obfuscated code into a 3 arguably more readable lines using a bitwise operations. And this was a front-end webapp.

Then again, more readable is subjective and some devs might see "<<" and get thrown off.

[onion2k]

A reasonable 'compromise' of 3 lines of code with 7 lines of comment to explain what it's doing would be my preference.

[throwaway2016a]

Or... and just throwing this out there... developers can take responsibility to know what bitwise operators do the same as they know what "+" does.

The three lines of code were:

for ( ... ) { x = x << y }

The developer was essential using an array of booleans to simulate a bitwise operator.

It is very sad that devs these days need a comment to know what that does. Would we expect 7 lines of comments if it was:

for ( ... ) { x = x + y; }

[onion2k]

developers can take responsibility to know what bitwise operators do the same as they know what "+" does

Yes but they won't. Pragmatically speaking adding a comment to explain a concept the next developer won't use very often means you won't need to answer their questions about it when they next need to modify that piece of code. That's a big win for you, and it means the other developer can carry on being productive.