Here at 7:22 he removes the N-gon on the gauge window. But is it worth it? I looked at a matcap before and after and the "all quad" solution is...bumpier. Looking at the N-gon's matcap it's quite smoother! :D
If the Ngon is not bothering anyone, let the poor thing be. Ngon's are like the Quasimodo of Notre Dame or like The Best in the hunted castle, treat them with kindness.
