Rule #1 of the moderator's handbook, is do not touch Satoshi's posts. I doubt anything was removed intentionally, although I don't know what post you are talking about in particular.
BTCTalk has probably the best staff on the internet. They never censor anything and generally leave everything alone to allow growth. Satoshi is the main creator and helped everyone and everything evolve. There is no reason for them to censor anything from Satoshi. Satoshi has documented in the original Bitcoin whitepaper along with his posts some critical info that needs to be preserved and protected. Thanks to the staff for their time effort and attitude.
If it was an accident or the moderator was just trying to be helpful and made a mistake, can it be undone?