What do I think, what do I know?
I know Ollie Mealing is insanely creative when it comes to magic and creates his own material, and sells very little of it.
I know "Open Prediction" is a plot, not a trick in and of itself. Meaning there are tons of methods for that particular plot, each having its own strengths and weaknesses.
I know Ollie works closely with Derren Brown so he must be quite good at what he does, and very likely has learned a thing or two from that particular master showman.
And I know he performed this very well. A card trick I actually enjoyed watching. A very rare thing indeed.
I think that it's quite likely he came up with a method on his own, so you're going to have trouble replicating it.
I personally think it's better to enjoy the performance rather than break down the method. It's so rare, once you start really learning a lot of magic, to see something that strikes home. The more you know, the less magical magic is. If you find something that really intrigues you, that really makes you feel like you've witnessed something magical - save that. You'll thank me later.
I also think that the only reasons to try to figure out the method are: 1) To prove you're smarter than him (ie: "I know how he did that." syndrome) or 2) to steal his trick. Neither of those are good things.
Please, please trust me when I say this: If you are serious about magic, and you are studying the methods and such, and you find something that gives you that feeling that inspired you in the first place: Leave it be. Just enjoy it.
