Do you know how the Saints graded those same performances? I think they are in the best position to most accurately grade those performances. I know their grades are the only ones that matter to them.
To an extent, yes. I've had several chats with scouts (both pro and collegiate departments) in house about various players. Generally the evaluation (this players does this good/bad) are the same for everyone. The valuation is where you have differences of opinion. EX: Can player overcome this. What's their ceiling? etc. There are also intangibles (especially on the mental side of things) that are incredibly difficult to quantify.