So the *other* purpose of the Hatzi Kaddish is a blessing after some amount of prayer. Which makes me think that saying that right after only one blessing, Hinei MaTov, is slightly not legit. Which means that even with the crowd it still wasn't appropriate.
Which means I have a hard time getting it right. Which means, damnit, I want to say it by myself. I'll call together a full chorus in my head for the responsive line. I need it. Forgive me, I am lazy.
Meanwhile, back at headquarters...