User blog comment:Hyp cos/Analysis - BEAF, FGH and SGH (part 1)/@comment-5150073-20131024160701/@comment-1605058-20131025105448

"Iff" isn't good to use here, because w2+n=w3[n]=(w+w2)[n]=w+w2[n]=w+w+n=w2+n.