I just noticed that Diago was awarded a Strunk and White badge one month after his last edit.
What happened? Did the requirements for the badge loosen? Did it just take a month to award it? Or is this an error?
Not knowing how the badge system works, this is only hearsay.
Each time an action occurs that could affect a badge, the badge criteria are re-evaluated. This means that undeletions could create badges for apparently no reason. Theoretical timeline:
TaDa! Suddenly he gets [Strunk and White] without having made an edit for over a month. I assume this could also work for Good Answer badges.