I think you're absolutely right. But the penultimate step is worth highlighting separately, the way the right lemma can render a proof obvious. Especially given

I think you're absolutely right. But the penultimate step is worth highlighting separately, the way the right lemma can render a proof obvious. Especially given how difficult a proposition this penultimate step is. It's like saying you want a better algorithm for multiplication when you use roman numerals. So I'll stand by my statement that the RFS's phrasing is -- not wrong, but rather -- misguided as stated. Or maybe "misleading" would be better, but that carries connotations of malice.