SWIG had real fun some time back when he added 35% H2O2 by drops into the ker plunking pot. Furious explosion of activity! Toss in a little more salt! Add a little more NaOH! watch it bubble!
Then someone posted in this thread and suggested peroxide destroyed meth by oxidizing it. That sounded like something SWIG would just prefer to avoid. He recalled that peroxide did reputedly damage the pseudo molecule, and one should not add that capful of peroxide to the reaction. He thought that peroxide in the ker plunk might destroy the unreacted pfed. He did several reactions, he told me, with the 35% peroxide and on each use noted no loss of yield and had great, clean meth with each reaction.
Problem is that he got very similar results with 3% peroxide, and with none. And he is hard put to say that the amount of unreacted pseudo was a problem at that time anyway.
He did recall how the addition of peroxide would have a color change effect on any gakk residing at the interface. The peroxide would cause a purplish to black stain in the gakk that dissappeared with stirring. The color reminded him of iodine, and he assumed the peroxide was acting on sodium iodide in the still fairly acidic polar layer and he was seeing some I2 precipitate then dissolve. The color change never seemed to happen after the polar layer became basic. It only happened at the start, when he first started basing the polar layer. At times the addition of H2O2 would result in a red coloration, which sometimes lasted for most of the ker plunk.
As to your other hypothesis about peroxide reducing iodopfed,etc. Geez would prefer to say nothing and be thought a fool than to post something which would remove any doubt.
Mostly harmless