Hmm. A comment that might increase my understanding when I write it, may not do so for your understanding when you read it.

It might help Fred, and leave Bill cold, whilst leading Harry right off down the garden path. It all comes back to the imprecision and variablility of interpretation of natural language. And that's before we get into the realms of social and cultural differences.

Yes, precisely. Working with other human beings is a pain, isn't it? Everywhere you turn, you're stuck with a certain amount of imprecision, even in questions like "does this code work?".