Yeah, I agree almost entirely with miketyson.
The GC writing staff are the writing equivalent of good strategists,
horrible tacticians. Very good at the "big picture" level but really bad on details.
And when you're being
this ambitious, you need to be
very good on the details for everything to come off well.
Yoshino should be a sounding board/adviser for an actual good writer.
His job should simply be to say "Hey, here's an idea!", and then have somebody else actually implement it (or rule it out, in more extreme cases).
That being said, I'm not sure how seriously we're supposed to take all of these characters. Ultimately, Daryl felt like little more than a plot device character to me (primarily a character to play needed roles in various conflicts, mostly antagonistic roles). And as a pure plot device character, I guess he was useful.