During those days of TV animation, Two key animators rarely work together on the same scene (there are exceptions). More often than not, one key animator has been in charge of a whole scene.
Also, "Kugatsusha (九月社)", which is on the staff list for this episode, Is an animation studio run by Yoshikazu Yasuhiko.

https://twitter.com/GENP37/status/1172795599873171456
Gen Sato (who belonged to "Kugatsusha") was sometimes in charge of key animation.
Although his name is not in the staff list of key animators in this work.

https://twitter.com/kozuma_/status/224693200034598914
Furthermore, based on Shinsaku Kozuma's remark, It seems that Yasuhiko was responsible for a large amount of the layout (and probably 1st key animation) in this work.
Reference: https://twitter.com/Time_Machine_Go/status/1040401553926942720

kiyotaka_chang said:
During those days of TV animation, Two key animators rarely work together on the same scene (there are exceptions). More often than not, one key animator has been in charge of a whole scene.
Also, "Kugatsusha (九月社)", which is on the staff list for this episode, Is an animation studio run by Yoshikazu Yasuhiko.

https://twitter.com/GENP37/status/1172795599873171456
Gen Sato (who belonged to "Kugatsusha") was sometimes in charge of key animation.
Although his name is not in the staff list of key animators in this work.

https://twitter.com/kozuma_/status/224693200034598914
Furthermore, based on Shinsaku Kozuma's remark, It seems that Yasuhiko was responsible for a large amount of the layout (and probably 1st key animation) in this work.
Reference: https://twitter.com/Time_Machine_Go/status/1040401553926942720

Yeah, all I saw for KA was

原画：兵頭敬　内田順久　九月社

So I assumed the effects heavy cuts ought to be Uchida given that I know him as a mecha/effects animator, and the human focused scenes Hyoudou, and then the September Company filling in the gaps on less laborious parts, but I wasn't sure. The explosion at the beginning of the episode and these smoke effects seems right for Uchida. I've never known Yas to touch effects.

https://twitter.com/norider1965/status/224694069283143680
https://twitter.com/kozuma_/status/224695354837319680
https://twitter.com/nakaR6/status/224698253399171072
From what they say, I guess that Yasuhiko did most of the scene layouts and the rough animation in this work. The key animators on the staff list seem to have worked in a similar way to the 2nd key animators in modern animation production. However, there are some details such as the form of "shadows", "highlights" and "smoke" that show the characteristics of the key animators in this work.

Alright, then I think it is probably worth adding him to the KA on all of these, perhaps with the exception of the opening explosion, that seems to me to be pure Uchida, I don't see why Yas would do just an explosion scene, but he probably had set out the basis for all the human parts in these cuts as a rough 1st KA. They are just talking about episode 1 then? Was this a trend throughout all of the episodes?

>Then I think it is probably worth adding him to the KA on all of these.
I think so, too.

>They are just talking about episode 1 then? Was this a trend throughout all of the episodes?
I think, They're talking about all of the episodes in this work.
https://twitter.com/deresuke1960/status/220088823357505536
Hiroyuki Yamada (山田浩之,who was the key animator on this work) also said that Yasuhiko did the all layouts and 1ST key animation.

However, the animation director was sometimes someone other than Yasuhiko, and Tsukasa Dokite was in charge of three episodes（EP15,EP21,EP23）.

By the way,
https://www.sakugabooru.com/post/show/43596
0:13~0:17,0:21~0:22,0:51~0:57,1:39~1:42,2:00~2:04
These are explosions drawn by Yasuhiko.
He uses "color shifts" to represent the "temperature changes" of the explosion.
This expression can be seen in the OP of "Giant Gorg"

That's a scary amount of work. But from what I've heard about Crusher Joe it checks out. Thanks, I didnt think of looking over his MSG genga and just assumed it would be all character stuff, that is a good reference for future episodes, as with the Gorg OP. Of course, I didn't mean that I didn't think that he could draw an explosion - just I was under the impression that he left that to others save very special cases. In this case I guess it's best to assume that he had his hands on everything then if so many people are saying so, so I'll source it all that way from now on.