Well, personally I know that in my writting I often hit "enter" and then try to start a new paragraph by hitting the "tab" key. . . unnoticing that I have now skipped down to the "SUBMIT MESSAGE" button on my browser I often keep typing, either not looking at the screen or expecting lag time and then after a word. . . I hit the spacebar. With my browser, as with most, this has the effect of activating the button which is highlited. . . and thus I get my message posted a few times rather than the one I had intended.