I have concluded that 51%H3PO2/I2 would not reduce ephedrine to methamphetamine. My idea is the addittion of the 51%H3PO2 to the standard redp4/I2 reaction as a substitute for the water added. After reading the hypo-acid synth over on rhodiums site, I noticed that the water content of the acid plays a part in the supposed reaction. My hypothesis is that the H3PO2 would provide the water needed for the reaction, as well as possibly increasing the concentration of HI, I think it might even lessen the amount of redp4 needed. These are just some ideas of the top of my head, no practical experiementation has been done.
The only time I have ever heard of anyone using 51%H3PO2/I2/redp4 was aqua girl, who's write ups were basically "I throw in a little of this, a pinch of that" she was never very scientific in her approach. She did however she did say it worked out really well, and that I believe, because of this I think it is worth looking into. I am more interested in the chemical equation/scientifc mechanism of such a reaction.
JUST BECAUSE I TALK ABOUT SOMETHING, DOES NOT MEAN THAT I HAVE ACTUALLY DONE IT, OR PLAN TO DO IT!