Originally posted by Michael Rubinstein:
...the difference between an assembly and Matrix was that Matrix was Al's coin effect that used cards as cover to effectuate an assembly.
Not to put too fine a point on it Dr. R. but I think the thing that differentiates Matrix from all it's clones, and it's predecessors, is not that the cards are used "as cover to effectuate an assembly", which is the case in so many Matrix-like tricks, but that the cards are used "to prevent manipulation". They are not there to help the assembly of coins but to make their movement impossible. Im sure you know this, and were speaking about method and not about the perceived effect, but Im also certain there are readers who dont see that distinction and we should make sure they do.
It amazes me when I see so many of the recent variations on David and Al's routines, that the people doing them clearly don't understand the originals. It just looks like they are sliding things around under their hands, or hiding something under the cards. This is most evident when you hear someone opine that a "shadow coins" assembly is superior to a "matrix" because you don't use cards to cover the coins.
Both effects are beautiful when done by someone who understands them. And awful when done, even competently, by someone doesn't.