It IS debatable, because the article specifically says,
"Our Founders, realizing the truth of the Christian doctrine of the inherent sinfulness of man, established a government in which power was divided at the federal level between three competing, contrary branches with specifically-defined powers. Further, political power was divided between what was supposed to be a relatively weak federal government and the state governments. The intention underlying this choice was to dilute the ability of any one man or group of people from being able to exercise power, naturally corruptible, over their fellow citizens."
Notice, it speaks of intentions, not results. What is inarguable is that the Founders who crafted our Constitution instituted these checks and balances as a means of diluting power. That was their purpose with it. As such, your whole argument is a rabbit trail.
Whether Patrick Henry thought it would actually work or not is really quite irrelevant to what the article actually said.
The framers and supporters of the Constitution were not limiting government--they were expanding government. They created whole new bodies and offices and powers of national government where there were none before. The "federalists" were for bigger, stronger government.
In a way, the Constitution was the first great American political boondoggle. It was created in secret. It didn't do what it was supposed to do, and once passed, it's impossible to get rid of it.