Let’s simplify that sentence and take another look: You wouldn’t say “The BYOD policy puts a strain on we,” right? So “us” is the correct answer.
For practice, let’s explore the chicken context: You’d say “There’s nobody here but us,” rather than “There’s nobody here but we” so “There’s nobody here but us chickens” is correct. Of course, if help desk workers or chickens are the subject, that changes things. You’d say “We help desk jockeys are not thrilled with the BYOD policy,” for example, and “We chickens would welcome a little company.”
“We” often appears in that type of construction because people who don’t have a firm grasp of pronoun use often think that the subjective pronoun ( I, she, he, they, we or whom) is more proper. The problem doesn’t tend to come up in simple sentences, like “He gave me a lecture on mobile security” but when sentences get even slightly complicated, such people tend to default to subjective pronouns. That’s called overcorrection, kids, and it’s just as wrong as any other type of error.
Here’s a quick reference on pronoun cases:
|he, she, it||him, her, it|
Victoria Rose offers further discussion of pronoun cases and chickens.
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