As an ESL I can tell you that it also depends on your exposure to English. Non-native English speakers are often taught and exposed to mostly (classical) literary works and/or formal speak (for example, math and science). It's one of the reasons why their speech might sound stilted in person, but "perfect" in writing. What you think is "colloquial and limited" might be considered "perfect native speak" by the ESLs who often don't get that kind of environmental exposure to English.

Does ESL stand for English as a secondary language ?

Is that in common usage ? I have never seen it used to designate a group of people.

> Does ESL stand for English as a secondary language ?

I believe so.

I picked up this usage (ESL as a descriptor of person) from forums and boards around the internet. Not sure how correct it is.

It is accurate and also still in use in academia. In every educational institution I have worked, "ESL" is used both verbally and in digital records.

It's been in use for a long time. I remember seeing it in the 70's in colleges that taught immigrants English for free in night classes.

I think they mean perfect as in flawless in its execution, relative to the context of comments in code.

Obviously comments don't need to be in MLA form, ya know?