I think he realized that most of the talent in the farm wasn't going to pan out, at least not along the specified timeline. With the pressure from Rogers to produce he didn't really have the option of a second rebuild. It didn't appear that we were a preferred destination for FA's, so he traded. In a few years (assuming he can get us in the playoffs and isn't fired), he'll probably take over as president and someone else will rebuild.
Really, in spite of a fairly high ranked farm, it hasn't produced a whole lot. With 2 or 3 exceptions, most of what we traded away looks like we made the right decision on.