Steve Lemmon- That netting has been used on teeing grounds at Pebble. It makes sense that MM would use it in collection areas in fairways too. What is rather amazing to witness (even the pros), are people who actually can't figure-out why that stuff is there. I have even seen several people try to move it, so they could play from that spot. I must say, it takes all of one's discipline, not to unload on any moron who is so unaware as to not realize that that is the manitenance g-d's way of saying "stay off!", Same would be true of anyone close enough to trip on the stuff.
As for the courses differences, from yesterday and today. While subtle, they are not small. The greens yesterday exemplified a couple of things; One, the nature of having a poa/bent mix. Possibly combined with some of the maintenance tricks Don Mahaffey illustrated. The better players seemed to come-up short on a lot of well struck putts. I think the patina mis-lead them, as to thier speed, and today they seem to be able to stroke it just that tad bit firmer to make them.
I don't ever recall seeing a usga course set-up, exemplifying the core principles better than this year's at SHGC. From the textures and colors, to the line of charm's visual nastiness, and, the bounce of the ball. The entirty of the package has made me a believer in SHGC.