Hey guys, happy to clarify. The short answer: the plots are the same, but the methods are not. Double Cross has a few special features that make it totally self-contained within the Sharpie, including placement of the mark on the spectator, enabling you to present every aspect of this effect in the most covert, deceptive manner possible.
Don't want to say too much more in a public forum (as not to expose Double Cross or any other effect) - but if you have any specific questions, feel free to contact our support crew anytime.
Double Cross is - and I'm not alone in this thought - the best, most PRACTICAL execution of this plot I've seen. You put the Sharpie in your pocket, and you're ready to go.