Polish you don't layer, it's your LSP's you layer :) Polish in its nature is abrasive, and as such won't layer. Megs #16 as a paste wax will layer to some degree, and always benefits from a double coat minimum (mainly to ensure you've not missed any bits).
That said, there seems to be a love of all things German in that picture :D The what looks like an SLK reflection looks good in the door of the A3!