From what I understand, the production team for 86 originally planned to have a break week in December. November 13’s break wasn’t originally planned and is instead the result of production delays. This isn’t too surprising after last week’s episode; minor signs of that could be seen in episode 16, as a handful of close shots (especially of Shin) seemed less refined than normal. Hence we have a “Visual Commentary Special Episode.” So is it worth watching?
If you normally like commentary extras on DVD/Blu-Ray releases (which I expect this episode will eventually be) or want to see the seiyuu (Japanese voice actors) behind the voices, then yes. Otherwise, no.
The episode features Shoya Chiba, Misaki Kuno, and Seiichiro Yamashita, the voices for Shin, Frederica, and Raiden, respectively. They comment on clips selected from episodes 12-16 (though 16 wasn’t actually used) and provide some insight into how they played and perceived the characters. While some of it was interesting, nothing was eye-opening. They finish the episode by featuring the Reginleif models which are newly-available in Japan. The one takeaway from all of this is that, contrary to the character he plays, Chiba seems well-suited to being a talk/commentary show host.
So yeah, this is skippable.