When lip synching, yes your mic is to your mouth AS IF you are singing. Normally, in LIVE performances, there is a difference in sound. For instance, when he did Black or White, there was a significant DIFFERENCE in how Michael sounded AND how the guy sounded doing the "rap". The goy performing the "rap" sounded LIVE.
Also, with concerts, why didn't he (from what I saw) ask for audience participation? He continued the songs, there were not ANY interruptions, so to speak. Everything, was "choreographed" for the lack of a better word. What I heard were tracks being played in the background. Yes, he did have a band/orchestra overhead. And....?
I don't know, maybe, I'm use to people like Sade, Maze, Jill Scott, Kelly Price, The O'jays, Patti, and others giving me a performance WITHOUT lip synching at a concert.

With them, you can TELL without a doubt that they are NOT lip synching. Just because a person stands in front of a crowd, with a mic in his or her hand, and a band "playing" instruments, does not mean that they are actually singing.
I didn't see ALL of it, but what I did see, he WAS lip synching.
Even if he wasn't ENTIRELY lip synching, he should have had a BETTER sound engineer/technician, because it (the sound) was WACK for ALL the money people had to spend on those tickets!
IMO!