I have a part that’s welded to the character. It’s massless, has a RootPriority of -127, and is unanchored. Despite all these measures, it becomes the AssemblyRootPart of the character Assembly whenever it’s Rope is Enabled.
I see no mention of this behavior under the Constraints docs, nor in the graph shown in the Assemblies docs, and thankfully not.
Expected behavior
I expect objects bearing constraints to be treated no differently than those not bearing constraints in assembly tree sorting. In my video the toolmainpart should never be the AssemblyRootPart, as the character’s HumanoidRootPart is clearly a better candidate.