I'm also curious as to what gave me away for my personality type. :-P
I'm going to announce ahead of time that I apologise for anything that sounds remotely insulting.
When I think about it, I should at least have been able to consider that Reon is Feeling oriented too with his ideologies. The rest was a mystery, however.
That is also one of the things that gave you away, Pengu, as I realised during the NPO/NLO situation that you stood firmly with what you perceived to be right, thus making you an idealist.
Let me just again note that I'm not trying to be insulting when I say that. You are definitely one of the cleverest people here, especially in a social context, able to gain insights into other people that I really struggle to do. However, often times, you can be swayed away from doing what you objectively know should probably be done because it doesn't feel right. I could see that you also didn't handle socially stressful and heated situations well, as you quickly became fatigued by them, and instead of showing outright anger, you are more likely to become increasingly fatigued and hurt as you try to bottle up your anger, which gave away the I and F.
You think in broad, general terms, which gave away the N, and you also have no trouble coming to a concrete decision or working out a concrete plan and following schedules, which gave away the J. Your insanely good organisational skills also hint at the J.