Makes sense to me. I mean, in general, aren't the effects of burn-in supposed to decrease or minimize the bad stuff (e.g., sibilance) and refine or add to the good (e.g., greater clarity, transparency, increase soundstage, tighten the bass etc.)?
I don't have any feelings about burn-in one way or the other, as I've never done it. I'm too lazy and impatient to burn-in my gear and not smart enough to remember what the stuff sounded like 400 hours ago compared to now to make any meaningful evaluations. To paraphrase Ali, "Burn-in? If that's good, I'm it."