alright, this did change over time. to restore it add 32 (http://kb.mozillazine.org/Browser.urlbar.default.behavior) to the mask of values for browser.urlbar.default.behavior, which doesn't search on focus, only when you start typing
this behaviour was changed here: http://hg.mozilla.org/comm-central/rev/f3eda128cbd3
there is no way to restore the old behaviour for the search dialogue thats immediately visible, but for my usage that is fine, for now; but i'll keep looking for a way to do it.
is it reasonable to request that this bug be a feature request to restore the old behaviour? like making ubufox set that mask; i'm not sure on the visibility of the distinction, or whether people even notice the difference; but it is a good deal of daily aggravation, and into the future, remembering to change it in new profiles :|