Some input on how it could be split up (while simultaneously avoiding big changes to the current document):
Actually, the original intention was to specify how the actual “check for objections” step can work on the forum. See the oldest version of the original process (by clicking on the pencil and navigating to the oldest version). The “How to create a proposal” and “Reviewing decisions” sections in the current process were added later as part of restructuring etc.
In fact, the original driver was (though I put it into these words only recently, explanation here): “We don’t want to expect every team member to show up at the weekly meetings. Thus we need to check for objections in a way that enables people to contribute asynchronously.” This was fulfilled well by specifying how the “check for objections” step can work on the forum. (The rest is basic forum usage.) Anything we add beyond that is (mostly) waste towards this driver – thus it should be motivated by its own driver, and belongs in an additional document.
This is the tension that motivated introducing the wiki thing. I would argue that it relates only to the “How to create a proposal” section, and that this section along with the fix should become a new document.