[Sherlock smirked at John. He didn't carry himself like a soldier anymore. It was rather odd but there was no denying that this John was different from the one he knew.]

I thought that was probably the case. I'm sure you saw the other students and teachers on your way in. This is a school-wide phenomenon. I'm very curious to find out what I'm doing here, though. By my best guess, I've taken the place of the Sherlock of this place somehow, same as you have come to occupy the body of my John. The only difference appears to be that your memories superseded John's while your Sherlock's appended themselves to my own. Might just be a matter of superior intellect but a wider study would be needed and is available.