> If you're just going to use it once, or if all usages have `[it=foobar]`, I don't think you'd do it.
If you never pulled out code into its own separate function just in order to name some lines of code, you should give it a try. You can avoid a lot of comments and/or confusion by just structuring your code in a way that allows you to name lines of code as concepts and abstractions. No need for it to happen more than once for you to do so.
It wasn't referring to the specific identifier "it" here, but more in general as I took your point to mainly be about "if there's a benefit to using other values for X in other contexts", meaning that putting things into variables only serves the functionality of reuse in different contexts, not also to name passages of code.
If you never pulled out code into its own separate function just in order to name some lines of code, you should give it a try. You can avoid a lot of comments and/or confusion by just structuring your code in a way that allows you to name lines of code as concepts and abstractions. No need for it to happen more than once for you to do so.