Jas, it seems like you have skinnier tires with the tire pressure at 80 compared to my 700x32's at 60 psi. so your ride will be a little more bumpy. I would, however keep it on locked because on the streets, 90-95% of the time the surface will be flat. With the amount of grip of your tires, you will want to keep it locked anyway and save the open fork for the trails. I tried riding with the fork open on the road and at times, the suspension would dip while in the middle of a turn..it is actually quite dangerous IMO.
The best advice i can give you on top of the other awesome advice you have already been given(Victoria, WC89, Richard, and jsdavis) is when you see a pot hole, try to lift your handle bars so it goes over the put hole and not "hit" the pot hole giving a shock to your wrists and joints. Practice doing this on little bumps and you will get quite good at it i promise. When you lift the handlebars(front tires) to avoid small bumps while riding, you not only avoid some harshness, but your rear tire will just float over the bump(not so harsh) so i wouldn't worry about feeling anything at the back. Like jsdavis said, your legs will absorb the rear bumps. Happy Riding!