From another Pooh-bah's perspective, and without any ill-feelings (what's done is done), I really feel that "telling" people to use the search feature should be completely and utterly discouraged.
I mean, since a new thread has already been created, we must take the opportunity to be informative in the new thread so that it becomes a useful resource to everyone else. At the _VERY_ least, one should include a link to all relevant threads so that the next 50 readers don't have to "search". Old threads also become, old, so try and include new and updated information aswell so people don't have to dig for it under 20 pages from the old thread.
If you're going to tell someone to use the search feature, do so only after having written a lengthy and completely helpful response, including links and references, then followed by a kind reminder of how to effectively utilize this site and its search function. Anything less is just a waste of space and shows lazyness on our part (telling lazy people not to be lazy is JUST as lazy). Teach by example, not by repremand.