Ok, I read the theory on Okiya being Suichi Akai in disguise. The reasoning looks good. I only have 1 thing in mind: Okiya is an engineering graduate student. It's a highly specialized skill, not something easy to pretend to be. Undergraduate student, maybe, but graduate? He is also pursuing a doctorate, so he is a Phd student. It make sense also from his age & the fact that he do researches (some masters students also do research in their field, but not all of them do, & the ones that do, the level of research differ from Phd students). If you are Shuichi Akai, you might not have the time to study engineering in your spare time, while you are infiltrating BO, being an FBI member, & so on.
I also don't really like how Gosho lump scientists & engineers together, like they are all interchangable. Shiho is a scientist, possibly a biochemist. Okiya is an engineer. If he is bourbon, he might be a computer engineer, but he might also majors in unrelated-to-BO fields, like civil, industrial, & so on. Agasa is probably a mechanical or electrical engineer, since he tend to invent stuffs with electronic wiring? He also invent the bomb used in one of the cases, which is another example of science generalization (is it seven rainbows? I forgot the name).
The point is, they are all have their own field. Being an expert in one doesn't mean they are an expert in others as well. The science & engineering fields are a broad area anyway. Just because Agasa can make a bow tie that can imitate people's voices doesn't mean he can make a bomb. Just because Okiya is an engineering student doesn't mean that he'll be able to help Agasa's research if their field are not connected. I'm referring to the red, white, & yellow case - the kids mentioned that Agasa has a doctoral in engineering, to which Okiya replied that he is working towards a doctoral degree in engineering.
Any thoughts on this?

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