I once saw David Berglas interviewed where he described the extensive preparation he put into making
a one-off effect.
Johnson and Berglas share that ethos. It's all about giving your
audience the wow moment - the look on their face.
I've only used the bonus effect so far,
and the reaction when they realise the card is in the chocolate bar makes going to the trouble to
prep worthwhile. Kieron is a creative genius!