First, I want to say that I am in full agreement with the spirit of the entry on
the sensible way to view comments in the Multiply Blog.
All the same it's pretty hard to get people to thread when there's a big open "Add a Comment" box at the foot of the page, so my suggestion is for the author of a blog entry to have the freedom to turn it off for that blog only, or even for their own site on Multiply. "House rules" if you like.
It would still be possible to reply as before by hitting the first reply link, so no freedom is lost, and those who want to keep an easy reply box open for their visitors can, simply by leaving things as they are.