It's not being lazy if there's an inconvenience. It's definitely not a major issue, but it's one of those small ones that can be bothersome.
Say I open three threads, I type a response to the first and submit. Refresh the other two threads to see if there are new posts, then I type another response, but I have to highlight and copy the response then refresh before posting, repeat.
I don't know about you, but when I click on a section I prefer to open all threads that might interest me, instead of opening one at a time. It's a time saver, and if the timer automatically went away it'd save more time.