A negative is not yet anything in and of itself, unless you make the bizarre choice to exhibit backlit original negatives. It is only a step along the way to a final... something. Attempting to determine loss from that neg is a path requiring much more careful criteria. I'd think you have to decide what you want your final manifestation to be then study the best route to get there from the neg... it's called mastering your craft. Every option entails some kind of potential compromise I suppose, and you want a result that moves beyond calling attention to them. Many of the most beautiful processes we have throw something away during progress toward final.
The post I put up some years back showing those comparisons was done for very specific reasons, none of them to make judgment unless on very strict and stated criteria. They have often been used for unintended purposes and many have criticized them based on their own agendas, but I hope they have been useful occasionally, they are losing relevance as technology progresses. But Paul is right, their relevance in this thread is minimal, without comparing to a "better" scan, or something that represents the unadulterated quality of the neg... and how can we do that without scanning it? The only peripheral relevance is that amongst the processes shown, scanned or not, there is loss amongst them all on paper, for what that's worth.
Tyler