teemo's bush passive

I just played a game going top against teemo, as rumble. In the beginning, i was in the bush, waiting for teemo. He got in range, i attacked, and he attacked me back.** In-Between** teemo's autos, he would disappear, causing me to stop auto attacking him. Then he would reappear, and let off a few autos, before disappearing again, before his next auto.

Is that how his passive is supposed to work? He just disappears** while attacking** people? Or vanishes in-between the enemies auto attacks? I'm not sure if it's a bug, or if that's how it is supposed to be, but it's not how i remember him working when i play teemo, so that's why i ask.