Use SharePoint designer to modify the view. This will make the changes for the specific instance of that discussion board.
If you need to make the changes to the view for all discussion boards, you can either
a) edit the schema.xml's CAML for the discussion board list that is located at
C:\Program Files\Common Files\Microsoft Shared\web server extensions\...
(Trying to answer from both an On-Prem and Online context here...)
What you're describing though isn't so much a memory leak as a performance degradation, which you certainly can do. Some examples off the top of my head: