I asked Larry Ebersold, who was master distiller at Lawrenceburg under Seagram's and developed the 95% rye recipe, about the small amount of malt. He said that's enough. Why that's enough is because they use supplemental enzymes. They are not using malted rye. I know this because Ebersold told me the original recipe was 100% rye, 5% of which was malted, but the accountants decided malted rye was too expensive.
Perhaps because of the success of MGP's rye, micro-distilleries have duplicated that mash bill. There's nothing wrong with that.