Losing the privilege to correct / modify the original post in the threads is more harmful than beneficial.

I understand that, in the body of the thread, you don't want to disrupt the chronology of the posts with members' corrections well after the time of posting.

Often, however, the original post of a thread needs to be modified / added to when a member chooses to keep the data organized so others won't have to wade through the entire thread to figure everything out.