Meh, oddly, I can actually see that particular strategy working quite well. Revolutionary War era muskets were notoriously inaccurate - shot a few of them myself and it's difficult to even hit a target, much less hit it with any accuracy. The typical firearms training back then, as far as aiming goes, consisted of "point in general direction of large mass of enemies and fire away", which was effective for the time and tactics used, but that's also a good portion of the reason the Americans, once they started using more guerrilla warfare, were able to win battles. It's also why the invention of the Kentucky longrifle changed so much during the war; the rifling in the barrel made the gun significantly more accurate than the traditional musket, allowing American snipers to pick off English officers with relative ease (by which I mean they were still incredibly inaccurate).
In this case, it's not surprising he was able to avoid the first volley via his horse and luck, avoid the second with the well-placed rock, and then once he got in close... Well, four foot long musket/bayonet combinations are closer to spear length than sword length, but also quite a bit heavier and more difficult to wield effectively. Against a skilled melee fighter they wouldn't stand any sort of chance.
So while yes, he was lucky as shit, and probably could've killed his target with a well-placed arrow while hidden from sight, his actions there were definitely plausible (if still lucky) and weren't a bad tactic for the time period. That said, I also wish we could see some more neutrality in the war. Being American myself, I tend to subscribe to the philosophy that fighting for our freedom is a good thing and we were on the side of "right", but that doesn't change Connor's motivations or the direction I thought the game would be taking. Marketing it as Patriot Porn will only go so far.