Hi Roger,
I just read your essay, and while I am not a mathematician (I do study physics) your argument totally makes sense to me.
Have you considered discussing this with some mathematicians? If you have but your argument was dismissed without a solid reason (e.g. proof) for why it has no merit, I would go to another mathematician.
Unfortunately my knowledge in this area is very little, but if your argument is repeatedly dismissed by mathematicians without solid reason, then I suspect that you may have discovered a novel distinction that is not yet part of our established mathematical knowledge.
In that case, I would totally change the perspective, or punchline of your argument. Instead of framing it as a criticism of sloppy mathematical thought experimentation, I would frame it as the discovery of a novel distinction between infinities, namely those, coming from a common set that has globally fixed relations between its members, and for which, for instance, ratios would be meaningful, and others for which such relations are undefined.
If you can derive interesting mathematics from this new distinction, then it is more likely that it will become part of established mathematical knowledge, and if it ever does become part of established mathematical knowledge, your original argument will be that much more forceful.
Unlike in physics, in mathematics you make up the ground rules from which to derive new results and prove new theorems , and I believe one of the best ways to do this is to introduce new distinctions. This reminds me of a brand new announcement of the solution a long-standing very difficult conjecture by a mathematician, who, in order to solve it, created in effect his own mathematical universe. You can read more about here:
http://www.math.columbia.edu/~woit/wordpress/?p=5104
The only criticism I have (and it has no bearing on the merits of your argument) is your highly unorthodox usage of the term "reference Frame". I would encourage you to consider using different terminology as this may put off people and deter them from considering your argument further.
To me, a more appropriate term would be "reference standard" (typically we would consider a ruler or a clock as a reference standard, and that aspect of the observer which allows him to obtain information about the world a reference frame), but other terms might serve as well.
It is probably very rare that a non-mathematician discovers a novel mathematical distinction, especially if it has implications for physics, and I find it very interesting that, finding myself in this regard in a similar situation as you, I came across your work. If you are interested, you can watch a video where I introduce a simple mathematical distinction which is as yet currently unrecognized (to my best knowledge) in the first 7 minutes or so of a talk I gave at a quantum physics conference. I believe that recognizing the distinction has profound importance for understanding the meaning behind the mathematical formalism of quantum mechanics.
http://youtu.be/GurBISsM308
My essay also contains an illustration of this distinction in a more accessible way.
I'm glad I came across your paper, it is unfortunate that your argument is not widely appreciated (I know exactly how that feels), I sincerely hope that this will change.
All the best,
Armin