I once had a presentation trainer who would count the superfluous filler words we tend to use to win time when speaking without a script, er, um and ah were all hot targets. It’s remarkably difficult to remove these, however like most things it’s about being mindful of habits we develop. I agree that just is a nasty habit, it’s got this faux-politeness to it that seeks to excuse or minimise — often where this is entirely unnecessary, like some secret cousin of the meaningless sorry that gets rolled out hundreds of times daily. To me it’s fascinating how language mutates in a native speaker environment like the UK where we are overloaded with verbiage from all sides — living abroad my daily language habits aren’t influence by the conversations that form habits, which means when I come back I notice them and wonder where they came from? I bet if we made lists of our most used words that list would surprise us — maybe that’s a list worth making?