BBS posts. These are from a series of posts between PCB's trial and full version.
>Q.「アリス」は紅魔郷以前の東方シリーズに登場していたキャラなのですか?
A.アリスは東方怪綺談(シリーズ第5弾)でも3面ボスでした。
特に関連性は無いし、思いっきり別人です(^^;ので気にしなくても大丈夫ですよ。
Q: Is Alice a character from the pre-EoSD Touhou series?
A: Alice is the 3rd stage boss from Mystic Square (the 5th game).
They aren't particularly related; you can completely think of them as different people, so don't worry about it.
> Q.「アリス」は怪奇談のアリスと本当に関係ないんですか?
A.一応、同一人物ですが、ストーリー的には一切関係ありません。
妖々夢のストーリー的にも、まるで重要な位置にいません。
(というか妖々夢体験版に出てくるキャラは、全員ストーリーに無関係です(笑))
Q: Alice really doesn't have any connection to Mystic Square's Alice?
A: More or less they are the same character, but story-wise they are completely unrelated.
She doesn't play any important role in PCB's story either.
(Or rather, none of the characters that appear in the trial have anything to do with the story lol)
> Q.「幻想郷」旧作を知らないのですが、霊夢とアリスの過去になにが・・・?
A.基本的に、ストーリーに関係するキャラは全て紅魔郷以降になります。
一応、紅魔郷から全体の設定を一掃したので、新シリーズみたいなもんだと
思っていただけると(^^;
Q: I haven't played the old works, but was there something with Reimu and Alice in the past?
A: Basically, all of the story-relevant characters have become the ones from EoSD and on.
More or less, since EoSD the entire setting has been swept clean, so if you could, please think of it like a new series.
Note that despite using the wording "same character" and "story-wise" above, it should be made clear that he's saying Windows Alice and PC-98 Alice are not the same person, but are conceptually the same character. He is reusing the template of Alice as this character, so while they are both conceptually "Alice", she is not tangibly related to the Alice you see in MS. ZUN uses the word "story" a lot here to talk about what we might talk of as worldbuilding, because at the time ZUN wasn't really thinking much about worldbuilding but rather splitting things into basically "story" and "filler"; only later on going back to take these elements and fold them back into the bigger picture.
He probably never did, since his statements in recent interviews like AWA 2013 contradict that "clean sweep" thing.
No it doesn't. He stated the same methodology he's been working under since forever.
Q: Is PC-98 canon?
A: The world they?re set in is the same. However, when I first started making Touhou, I didn?t think I would keep making new games as long as I did, so I?m aware there may be some contradictions. In those cases, please take the latest games as more correct.
You're going to run into major roadblocks without some seriously intense confirmation bias, if your goal is to show that PC-98 is "canon", whatever you actually mean by that.