I watched a demo at Torrey Pines in California on the 18th green of the South course when it was raining off and on in July last year. They had taken cores and cleaned, looked like 3/8" maybe, top dressed and tried to drag the sand in. The sand was literally smeared over the entire green and looked like a real mess. To top it off, since it is a public course, they had play coming just four holes away. There were at least 30 of us watching, including superintendents, USGA, Pace Turf, and a bunch of suits, probably the mayor of San Diego, who knows. They brought out this turf brush and we all couldn't believe it. With the first pass all the sand disappeared and the aerification holes were full. They did some figure eight brushing then circled from the middle out. Wet sand or not, no sand was visible on that green within 20 minutes. Beautiful. Torrey Pines bought two on the spot and we bought one the next day. We don't get wet sand where we are very often but use this thing all the time. Probably the best money we have ever spent. The Calif/Nevada distributor is
http://www.turfbrush.com not sure who sells it where you are but they can guide you.