I really have to disagree with this interpretation. Even if you have a POD after the War of Independence, it will never be the bloodbath that Vietnam became, mainly because the level of technology isn't there yet.
With a POD of Britain winning the ARW, it is probable that the colonies would get independence. However, it isn't certain, and it's even less certain that the same colonies would rebel - particularly once the slavery divide sets in.
With a POD in the late 1760s, it's probably an even chance of independence or staying with Britain, but you don't need division to the point of personal union even then. Some representation of the Americans in the Commons, Lords, or the Privy Council could have bought a lot more time, and after that it all depends on world events. The independence brigade were in the minority for a long time. They only got supremacy in the argument because not only was Britain not giving enough political reform away, they weren't even giving gradualist reforms that would suggest the road of progress had been started down. Even without political reform, the removal of most of the offending policies could have probably bought a decade or two.