An ion H or H+ will be always 1850 times more heavy, 1850 times slower than an electron, that means 1850 times more probable to recombine before touching the counter electrode.
This would also be my first thought. H+ ions released and recombined at the counter electrode.
On second thought, how would this work in case of a reversed voltage polarity (applying a different metal strip combination)?
B.t.w. how hard would it be to replace the non plated iron by an aluminum strip to obtain the reversed polarity?