As for flash paper, a friend who is a restaurant worker was told (years ago) that they received complaints on the smell. He had
to quit using it.

I think the flash paper makes Super Nova look very magical.

Something will be lost in this awesome effect if the flash paper is removed, and
IMO to remove the flash paper would ruin the effect.
Mr Schneider put allot of effort, time and thought into this effect.
People who don't like or want to use flash paper should figure out a method for themselves.
That's what being a Magi is, being creative. Thinking for oneself.

It's wonderful in its current state. I wouldn't change a thing. If one can't do it with flash paper, don't do it. Seriously, what is a high diving act without the pool of water?

Near the beginning of the 20th century, physicians thought that they could have a theory (in a very short time)that will explain all the events of the universe. emselves.

Now, they think that , with each answer, comes an other question...
It's an endless quest like in magic : new creations, news principles (not very common)...
Quantum mechanic, relativity, thermodynamic come from very simple and basic idea. then they become more complex as they construct.
The "problem" with simples things is that, when we combine them, it becomes complex. It's not really a problem, rather a beautifull thing... like the effect you show in the movie.
The effect is really good. It talks to the part of our mind that like dissect method.
If you go on working on it, sure it will talks to the part of our mind that like to marvel.
I hope we can see that in the futur with this trick as you did with a lot of routine
in others words, I hope you will keep working on it (I like more the vanish of the coin than the lay down of the cards)

Al
You are a true Master!!

Could this be accomplished using a coin box (with the lid set aside) and four coins?

To be fair, all I was looking at is a way to carry the coins all prepared - and the wallets seemed a natural cover for the necessary. Getting the trick started in context was the challenge I saw in doing the thing.

I have found that not too many places today will let you use any type of fire because of the liabilities involved.