You say it exactly right. This Combine has a lot of theatric value for fans and media, but for teams it is a lot about confirmation, about medicals, and about finding out about the person himself.
I know nothing more than what the media tells me. Sometimes (rarely) I'll watch a guy play collegically for some reason of interest and draw my conclusions based on what my eye tells me, but I am untrained and cannot see the intricate stuff that guys like you spot.
And, not matter how good we might be a seeing certain traits, there's so much more in depth that scouts know about that the public doesn't.