In general, no: most duplicates stay around. Having multiple copies of the same question with different wording is useful as search fodder, because people looking for an answer may use different wording too.
That's good to see that they actually have the right rules, but I've used it many times where my questions were closed simply for appearing similar to others (when I did not even find the others in my search results). I suppose the mods can be overzealous.
