"Sorry, I meant for it to come off sounding friendlier than that."  Lu-Lu apologized, shrugging.  "Like the kind of friendly competition that spurs us on to do better than we would have otherwise, rather than the kind where we get so caught up in beating each other that we lose sight of our greater goals.  I certainly wasn't trying to call your competence into question, either, merely pointing out that I have training in this area that you lack."