Lots of carbon in the brown stuff and nitrogen in the green material. I've never used this method as I don't have enough of the green stuff compared to the brown to do it. If you've got the proper ratios of green and brown materials try it. The compost pile should be damp, not wet, just damp like a 'wrung out sponge'. If you grab a handful and can squeeze water out of it, it's too wet.
Some people water their piles.
I don't on a regular basis although I'll turn the hose on it while I'm watering the garden in July or August. Back to the top. One of the neighbours down the road has one of those manicured places that much money buys. Anyway, come garbage day all his nice green lawn clippings are at the curb in approved recycling plastic bags. I saved the city the trouble and recycled them myself.