Thanks! Between the duck being a "Wind"-up toy, the fan("Wind)s persisting and "Re"peating through levels, and clocks "Rewind"ing fans to reverse them, we might have been a little heavy-handed on the theme.
As for 4-3 and 4-2, that's something we found out about late in the dev cycle, but we decided to keep it that way for extra player options. There's a way to beat the levels while using each build object, but kudos to you for figuring out the "secret" way!