Let's clarify that the spectator will name a card and it's in your hand. That being said, you will
give a little instruction along the way to help the spectator in their choices. The gimmick, to me,
is very unconvincing close up. Blake gives some ideas on handling, but they involve your hands at a
slightly odd configuration. In the stage or single-person version, you are supposed to handle the
gimmick a little more casually, but unless you do this on stage it's going to be obvious there's
something going on.
The concept is sound, it's just easier to do this with a slight
adjustment of your guidance and actually end with one card you can hand out and walk away rather
than use the gimmick. You will end dirty here and have to clean up rather quickly in a close up
situation. I understand you can repeat this and have a slightly different outcome, yet how often
does a magician repeat an effect for the same crowd?
The gimmick is well-made and should
last a good while. Credit goes to Blake for giving you something that should hold up to use.
Joshua Jay's "Inferno" uses a similar method and ends a whole lot cleaner. Or you can just use
common sense if you have a little knowledge and end clean with a regular card. If you do it right,
to the spectator the end result is ultimately the same and they'll never know the difference in how
many cards they got to actually choose from.