[spangry]

Unfortunately I have but only one upvote to give. This is very important if you're performing a usability / ergonomics study. Context matters a great deal. The parent poster is also quite correct about it being invasive: although not absolutely necessary, ideally you'd observe the user in whatever context they happen to use Rust (e.g. at their workplace or in their home). Lab studies are still valuable too, but you might miss some context due to the artificial setting.