Y'know, Prongs, I've been thinking lately. Maybe you were too hard on Harry about naming his kid after Snivvy.
Imagine if Snape went and had a kid (or gave birth to one, we all knew it'd happen sooner or later) and named it James. James Snape. Doesn't it disgust you? Now think about how our good friend Severus must feel knowing that, somewhere out there, there's a Potter with his name attached.
Cor, that must get up his nose (not that it's a small target, mind.)