again, two layers on the turf CAN be better (not always, necessarily) depending on the heat and humidity.
ever notice that when you apply the cement to the ski, then to the turf, that the turf is dry in about half the time it takes for the ski to dry? its not always the case, but sometimes it is. well, before the turf cement dries too much as youre waiting for the ski cement to dry, its a good idea to add a second layer. youre not covering up the first layer. youre 'revitalizing' it (making it wet again) by applying the second coat.
thats my theory and im sticking (no pun in ten did) to it!