FWIw, My 1971 K1 (General Export) has the very same handlebar than sgt. Pinback. I even dropped the bike a few years back and bought the very same through DSS. Pricey but originality doesn't come cheap.
I have a 1993 CB Seven Fifty (european version of the american Nighthawk) and I notice the difference very much when I switch from one to another. The Four has higher, wider handlebar. I should say that at the beginning it feels a little awkward, just like if you were riding a cruiser. The position doesn't call for "spirited riding" even when you know you can go fast with a 750. After some miles you forget about the riding position.
Never noticed anything wrong regarding the position until I got the Seven Fifty. Until then, the Four was, well, as perfect as it can be. For spirited riding I have the Seven Fifty; by now I will keep the Four stock, but I admit that an slightly lower and narrower handlebar would look great.