Read further in the article.
I was responding to his argument that the applications could limit the topics. I don't think they can with any effect.
He makes a further point that individual states could pass laws to punish a delegate who voted for an unauthorized proposal, but that's speculation and it's very unlikely many states would do it.
More to the point, the topics that are authorized by the applications are so broad you could figure a way introduce almost any issue under their umbrella.