Yeah, that’s sorta the gist of it, there’s not much to it.
I include an extra, redundant /s mostly out of habit in case it flies over someone’s head who decides to reply seriously. I’ve had that awkward thing happen before. But as one of my professors used to say, “nothing is obvious” so I’ve taken that to the bank.
I know the feeling. I’ve also been given the stern “don’t say anything” look. But joke’s on them, because I neither know enough to debunk the most random claims on the spot, nor know how to synthesize a semester worth of college in five sentences and be understood perfectly every time.