I see many potential issues with this setup:
centered inside a clear glass tumbler
Is the tumbler of uniform thickness? To what degree of accuracy?
Is the tumbler round, square, hexagonal, etc?
Is it oriented exactly the same relative to the 0 degree target each time?
To what degree of accuracy is the candle "centered"?
How uniform is each candle in circumference?
How uniform is each candle in height?
How uniform is the thickness of the wick for each candle?
Is the wick centered in the candle?
Does it bend?
How is the candle lit?
Is it done from the same side/angle each time?
Is it lit before or after the wax ring is placed on the tumbler?
Was the tumbler either cleaned or replaced between each trial?
Does the person How do you ensure that the candle is truly vertical in the tumbler (a 1deg tilt is not visible to the eye).
Of each of these, have you measured the results they have on the apparatus?
so the wax ring just fits over the top, which centers the hole nicely"
How is this wax ring manufactured?
What are your QC controls for the ring?
How uniform is the thickness?
How uniform is the hole in the center?
Please define "centered nicely" in terms of measurements and statistical deviations.
Have you run tests that show if any of these questions influence where the disk melts?
where the wax first begins to melt (this is fairly easy and consistent to determine).
How?
The first drip?
The first 'soft spot?
How is 'judging' elimanated from this step (a requirement of the challenge)?
Who does this, the subject?
Is the person who does this aware of what the 0 point is?
Is the person who does this aware of whether this was a control or real trial?
The glass with the lit candle is positioned such that the flame is approximately at the eye level of the subject
How is the subject isolated thermally and atmospherically from the candle?
How is the subject isolated vibrationally from the candle? (an unintentional foot tap on the floor can be enough to vibrate a candle flame on a table top)
The wording of this is vague - is the glass moved
after the candle is lit, or is this merely descriptive?
the only touching of the glass occurs when the wax rings are changed out and I do this myself
The subject sets up the apparatus - this is bad!
so there was no time effect
Was the tumbler and other experimental apparatus (including the table the tumbler sat on) allowed to return to thermal equilibrium between each trial?
Is the experiment otherwise run identically when it is a control vs real trial?
I had the air conditioner off and the windows shut, thus no influence from a fan or breeze
Apparently the author does not recognize/understand the existence of convection currents caused by the heat of the candle, and which could be unconsciously manipulated by body position alone of the subject, let alone by their breath.
by setting a target at 0°
This is not clear. Is it the same position each time, or is it randomized?
Is it chosen before or after the candle is lit, and before or after the apparatus is set up (candle in tumbler, disk on top)?
Does the person who sets up the apparatus know where the target position will be?
Is this target position in any way consistant when compared to the orientation of the room?
subject is not deliberately attempting to alter the heat of the air from the flame with their breath
It's nice that deliberate fraud is not taking place, but as we know, many of these effects are quite unconscious. (dowsing - ideomotor effect, for example).
Also, this statement implies that the subject
could influence the candle, by not ruling it out, and, we can conclude, probably does influence it.
I don't think that would be possible anyway with this setup
No experimental evidence provided for this assertion.
I'll tell you what, give me this setup and 3 weeks to practice, and I will win the $1M under these conditions. I am pretty confident that I could cheat my way through this set up, so long as Randi wasn't there to ask the same kinds of questions that I posed above.
There are just too many independent, uncontrolled variables to conclude that the movement is not due to normal physical processes.
However, with all that, this design has a serious flaw - it does not measure flame movement. It measures heat convection - which is not necessarily the same thing at all. First you you would have to prove that this apparatus has a high correlation between flame movement and heat convection.
edited to add: When I say I could cheat my way through it, I am in no way suggesting that Beth Clarkson is cheating. I suspect faulty experimental design combined with unconscious factors.