Sirius in hiding and the letters flaw

[l3al3y_Doll_3]

No: HPFGUIDX 69315

If Sirius could never mention his whereabouts in his letters to 
Harry while in hiding, why bother using real names, if any? Assuming 
the letters found their way in the wrong hands, isn't it obvious the 
person would know Harry was in contact with Sirius? Therefore 
questioning Harry about it. I mean, there's only one Harry in the 
Wizarding World (England anyway), and most likely one Sirius. (We 
know there's one Harry because anytime the name Harry is mentioned 
in front of strangers, they automatically know it's Harry Potter.) 
In my oppinion, a pretty big mistake on JKR's part.


-Maritza