"Paul, you can start by writ..."

Paul, you can start by writing an objection as a comment, if it's a few paragraphs long. You can write a new comment for each new objection. If you want to make it detailed / add a vote, then creating a new page makes sense.

I agree that the website currently doesn't provide intuitive support for arguments; this will come in the near future. For this year we focused on explanation / presentation.