Certainly is all a matter of degree, but I think the point of the analogy is that the best you can hope to see is if the band can do the technical things without having to put it all together as a group to make music. When trying to evaluate even individual players, the point that was made is the level of competition. If I'm matched against a real dud, I'll not only accomplish more, I'll feel better about it and look better.
The second paragraph sums it up for me. You may not be able to tell how good a player is, but you certainly can tell if he's bad.
It is largely a war attrition where not doing obviously bad things ends up being a plus in a competitive situation. And level of competition certainly needs to be considered.
While you can't just look at the box score, see this guy had a sack, that guy make a pick, this other guy caught a TD pass and call it good, you can look at how
how he did it.
Take Hyde's pick, as one example. Whether the fault was the QB's or the receiver's, the fact of the matter is the opponent made a mistake. Would we say Hyde "made the play". Not really. What he did do is make a play on a free ball when the opportunity presented itself against first string players. You would not put it on par with a guy taking a contested ball on a good throw. And that's consistent with what we know about him...a steady, opportunistic DB who doesn't make many mistakes, but we would not consider him a play maker.
Take Fackrell's sack as another example. The OT #69 was Erle Ladson, a UDFA who been bouncing around training camps and practice squads for 3 years. On this particular play, for some inexplicable reason, Ladson's first step was to an inside setup, giving away the edge, and could not recover. That's opportunistic on Fackrell's part. It sure beats falling down or whiffing on the QB. But how often are first string opponents going to make that kind of mistake? Not often. The one thing I take away from that play is Fackrell's quick hand work shoving off the out of position tackle. The fact it was a sack is not very relevant.
Take Ringo's sack as another example. That was a sh*tty block as well. But Ringo showed good quickness looping inside. That's something to file away for some future compare and contrast, and to see if it can be repeated. Again, the fact it ended in a sack is not particularly relevant.