I don't see why not. You have to have support with each tier not matter if it is fondant or buttercream. You could do the tier separation with dummies covered with the ribbon and have dowels or bubble tea straws supporting each dummy/tier and you could still get a dowel through the middle also. If I have totally missed something on this and am totally wrong though someone more experienced please chime in.
2/23/12 at 3:23pm