He's having you do something that's meant to help Black? I imagine it will surely be accompanied by a healthy dose of superiourity. For Black, the best method for anything is likely the one that gets the job done, and for Snape, the best method is the one that gets the job done better than anyone else could do.

And - right, the portkey. Why would you ever I wish you wouldn't Well, I really, really hope they don't find themselves in a situation where they need to use it. It won't be easy to get another.