On the second coat, I paint soffits with a 3/8" or 1/2" lambswool roller, then backbrush just enough to knock down the stipple from the roller. According to Purdy, overbrushing paint exposes too much of the coating to the air, causing the resins to evaporate to fast. This leads to a rough or splotchy appearance. Also, on the second coat, to cut in, I use a Hyde CornerEase roller with a lambswool cover. The reason for brushing the first coat is to ensure that all cracks and crevices are filled with paint. Cutting in the second coat with the CornerEase, followed by rolling and backbrushing the second coat is faster than brushing. You can also use the CornerEase to roll in tight spots like the area around exterior light fixtures, etc. I put both the roller and the CornerEase on an extension pole and use a 5 gallon bucket with a grid to speed up the job. You have to be sure you keep a wet edge, so it's best to have 2 people when using this method, or rolling from joint to joint on plywood soffits (about 8 feet) if you do the job alone.