Hermione's Hats

[Robert Jones]

No: HPFGUIDX 88702

If you think Hermione doesn't make mistakes, here is an idea I 
posted last year:

How do the House Elves get freed?  It cannot be by merely touching 
clothing.  The Hogwarts students get their clothing cleaned, 
presumably by the House Elves.  In Book 1 chapter 5 when Harry 
receives his letter from Hogwarts, it says that the students should 
have their names in their clothes.  Why would this be if their 
clothes weren't somehow mixed up with other people's clothes, and it 
is only during cleaning that this would happen.  The clothes aren't 
cleaned magically wherever they drop them and left there.

The House Elves are freed only if their master hands them some 
clothing (like with Dobby at the end of COS).  Dobby treats Harry 
like a master in the scene in OOTP 27 where he warns Harry that 
Umbridge is coming to the Room of Requirement.  So presumably the 
students count as "masters."  But they still must hand clothing to 
the Elves to free them.  The Elves can pick up the dirty clothing of 
the students and clean them without being freed.  It is only being 
handed the clothing that counts.

So ... this means that the great Hermione Granger is making a 
mistake when she thinks that the hats she is knitting and leaving 
around the Gryffindor Common Room will free the House Elves.  How 
did she think her clothes were being cleaned for years?  The Elves 
can pick them up and nothing will happen.  But the Elves are still 
annoyed that someone is trying to trick them and so they do not 
clean the Common Room.