JKR hints at secret

[jakedjensen]

No: HPFGUIDX 72879

It is possible that this has been discussed already (searched archive 
and could not find anything...but still could be there).  I just 
watched the special features for the Harry Potter and the Chamber of 
Secrets DVD in which JKR and the screenwriter talk about converting 
the script to screen.  At one point, the screenwriter says something 
like, "well there was something I wanted to take out and I went to Jo 
and asked her if it was important and she said yes, that needs to 
stay because it is important for the whole series."

I just watched the movie again and I was trying to think what the 
screenwriter wanted to cut.  Here are a couple of criteria I have 
come up with:
1) it is probably a scene/character not significant to the plot of 
the Chamber of Secrets.  Something that can be taken out without 
impacting the immediate story.
2)  it is something that would not seem to be important (or why would 
the screenwriter consider cutting it).

Here are a couple of possibilities:
1) was Hagrid really in knockturn alley to by slug repellent?
2) the polyjuice potion stuff (really they don't find out much there)
3) Dobby regaining his freedom
4) Gilderoy Lockhart losing his memory

Any other ideas?
Jake