Xin Zhao/ Inhibitor issue?

In my last two games(Bot games) I noticed and confirmed that when I use Xin's 'Q' that when attacking Inhibitor it will not only take of a second for each strike(3), but do it until it times out.

This means I can use My "W" and GhostbLade to pop them over and over fast.

Last I checked, Xin's 'Q' didn't work on inhibs?