I read an interesting discussion with no definitive answer regarding the question, 'why is the past perfect used here' on the following excerpt from an acclaimed writer who received awards for the book this is taken from:

He pities his parents when they speak to him this way, for having no experience of being young and in love. He suspects that they are secretly glad when Ruth goes away to Oxford for a semester. She'd mentioned her interest in going there long ago, in the first weeks of their courtship, when the spring of junior year had felt like a remote speck on the horizon. She'd asked him if he minded if she applied, and though the idea of her being so far had made him queasy he'd said no, of course not, that twelve weeks go like that. (The Namesake by Jhumpa Lahiri)

Why is the past perfect used here, do you think?
Let's see the discussion first. I don't like being 'tested'.
I just finished this, and noticed that this happens more than once in the novel. I personally consider it an error, or at least a bit of sloppiness. I get the impression that maybe the decision for the novel to be in the present tense wasn't settled upon until later, and there are still a few places where she hasn't got everything perfect. Of course, in a normal, past-tense narrative, those sentences all sound perfectly natural. If there's any artistic intent and this is a conscious choice made by Lahiri, it's beyond me.