That's an interesting question in that some of the conversion steps are to deal with general misunderstanding and weak enforcement in 0.9 systems. For example, URI fragments were never really valid, but few people understood that so lots of 0.9 statements have them.

What if we say that the final product must be a valid 1.0 statement?

Or, given the context of this note, perhaps just state that the verb was originally a valid 0.9 verb, perhaps we should even enumerate those verbs here.