Terri's cut was likely a horizontal cut across the middle of the cylindrical cake to create two layers, whereas David's cut was likely a vertical cut that created a circle shape in the cake.
David's cut allowed him to create a stripe in his cake by removing a section of the cylindrical cake and filling it with frosting. Terri's cut allowed her to add a layer of frosting in the middle of the cake by separating the cylindrical cake into two layers and spreading frosting on the bottom layer before placing the top layer back on.
In summary, Terri's cut was different from David's cut in that it was a horizontal cut that allowed her to create a layer of frosting in the middle of the cake, while David's cut was a vertical cut that allowed him to create a stripe and fill it with frosting.