Depends on how patient I am at scrolling down the long list before I post a thread, so yes, multiples on the same topic does gum up the works, probably guilty of it myself.
This site has been plagued by "Me,Too" threads ever since I can remember. It happens usually when somebody sees a story or hears something that he considers thread-worthy and p!$$e$ all over himself to be the first to get it on the board before checking to see if it's already there. It's most common among people who are especially starved for recognition.