Thomo, Jack already covered most of this in his OP. One thing I will say though is once these threads get legs it becomes a full time job to moderate them. It wouldn't be uncommon for the Scully threads to grow by 5 pages in between Demonland visits for me on a busy day, and I visit several times a day. The other thing is that it's so painful to read that sometimes I just don't want to look. So unless someone devotes themselves to just sitting there watching the Scully thread all day and night, occasionally the threads are going to get more momentum than the mods can keep on top of.
The other thing is that I don't think a lot of pearls of wisdom have been lost in the locked threads have they?
And once again I implore people to use the "Report Post" button (bottom left of each post) to help make the job of monitoring poor posts easier.