What I don't get about this is why the memory wipe thing even matters
I mean the entire point is that this is a Great Being in a Matoran's body, who presumably has all sorts of fancy Great Being abilities and such
Is it really much of a stretch to say that he wasn't affected by a memory wipe that was presumably only intended to affect Matoran?
It's not like loads of ridiculous stuff hasn't happened in Bionicle before; saying "Kapura didn't actually lose his memory because Great Being magic" is actually pretty reasonable in comparison
Did you read my whole post? I answered that:
Yes, the mind wipe showed us that most likely the hidden GB only had whatever powers were in the form he took, no special abilities (besides, we don't know that GBs have powers of their own anyways; they're organic and probably like Agori and Glatorian, just very inventive). I tried to use an argument against it for my Onua entry, but it was conclusively disproven in later conversation and Greg's further clues. It's possible also that he might have some abilities (the original purpose in the story for the reveal would imply at least one), but the mindwipe doesn't seem like the sort of thing he would know to stop. To blend he would have to get in the pods, and it was a power Makuta invented, not something (like Toa elements) that the GB would have known of from the start.

Countless proof that Greg thinks things through? Greg hardly ever thinks things through. Usually, if some discrepancy comes up, Greg says "Earth science only applies to Bionicle when I want it to," or "Artistic license," or "Well, that's non-canon now," or "Because I accidentally made this Toa of Psionics a guy, I'm going to come up with a lame, sexist reason behind it to cover up my mistake." As far as the Great Being is concerned:
I'd have assumed that I'd be someone who would't attract attention from others around him, whereas Velika probably annoys a lot of people.
Well, I expected an answer like this. You can always think of exceptions -- I'm sure there's some; it's a highly complex story, which is part of why it ended. But I can't think of many. Top perhaps is the size numbers related to the giant robot... But Greg's always said things like that were his weakness, so yeah. In general, to anyone who's been following Greg's correspondence on here for years I think we can all see that Greg thinks these things through a lot. Given the vast numbers of non-contradictory answers he's given people over the years it's shocking, actually. I would go so far as to say he is brilliant at these things.

But human.

Also, he made a contest about this specifically, and his answer matches the one that most of we fans arrived at too from a long time of open debate, so it's pretty conclusive that this was thought through.
(I wonder if he had picked Velika from the start, though, or went with the popular answer?

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The answer about Earth science is saying a true fact -- that it's a fictional world with fictional physics. Also, there was a story rule against going into too technical of scientific explanations for the little kids. Sometimes that rule was applied inconsistently as I've often pointed out (esp. with Pohatu Nuva's mask), but it does make some sense, and it doesn't really preclude us from thinking through how they could work.
Artistic license doesn't have anything to do with Greg as far as I know; many people besides him worked on Bionicle and sometimes miscommunication happened. That's more of someone else not thinking it through as well as Greg did usually.
Decanonizing most things was to remove inconsistencies, so that's also an example of
more thinking, not less.

There may be exceptions though...
As for the Psionics thing, that was probably a bad choice in light of some fans' reactions, but Greg had no way of knowing they would react that way. This was discussed to death at the time; it was
not sexist (but this isn't the place to re-debate it; basically Bionicle has had elements assigned with genders since the start, which wasn't Greg's decision and was more about the target audience being boys than anything; I agree it wasn't the best way but it's what's there). It's possible he did accidently forget he'd just made the element female, but I doubt it. It was a recent revelation. More likely he wanted to explain why the GBs made the rest female (and BTW, he had already done this for water, and nobody complained about that, so he had no reason to think they would about Psionics -- this was clearly another case of the complainers being the ones not thinking it through and just having an emotional reaction superficially to part of it; still, in hindsight it would have been best not to give people anything to have such a reaction about).
Good point about Velika annoying people, but then lots of Matoran have different personalities than others, and I doubt they have a widespread understanding of anything like my Society Variety theory or anything lol, so they're probably annoyed all the time by many. It wouldn't be a reason for him to stand out too much. Also we know that Kazi was the one who was mainly annoyed by him. The others don't seem to have been. Also, who else could he have chosen that somehow wouldn't attract attention? His risk of attracting attention comes from his own personality, not from anything about being a poorly repaired Po-Matoran.

Also, why do you say that you would have assumed it? We're not really talking about merely assuming, are we? We're talking about thinking it through. Are you saying you didn't really think about it before now, by "would have"? (Which is fine, just seems like an odd wording if you're trying to say you thought it through more than Greg...

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