In the context of a work of fiction, the term canon denotes the material accepted as "official", in a fictional universe's fan base. It is often contrasted with, or used as the basis for, works of fan fiction, which are not considered canonical. It is used in two slightly different meanings: first, "it refers to the overall set of storylines, premises, settings, and characters offered by the source media text". In this sense, canon is "the original work from which the fan fiction author borrows," or "the original media on which the fan fictions are based."
Since it seems that even a direct post by Todd would not be accepted as "proof" one way or the other of whether a forum post qualifies as "canon" (especially written by someone who is sometimes posting as a fan and sometimes posting as a developer) then there's no sense in discussing it - especially since it invariably results in verbal fisticuffs.
This is why we can't have nice things.