This topic also brings up another question I have.
With the hobby of appreciating nihonto, how much of the value and perceived quality of a blade is due to subjective vs objective reasons?
For example, with my limited knowledge, objectively, collectors look at the tightness and color of the jigane, the activity in the hamon, the physical balance of the blade, no kizu/ware, etc.
However, there are subjective aspects also, such as the sori, the pattern of the jigane, the overall shape of the blade, the hamon style, etc.
Do seasoned collectors generally agree on the combination of subjective and objective aspects of a blade to determine its value? Or do they have quite varying degrees of preference? I guess that's where the papers come in, to give a consistency in the appraisal of a blade.