the melody naturally (at least to me) separates the alphabet into a few groups
It’s not just you! (And FWIW, it’s actually the rhythm: with the exception of W-X, the last letter of each group is held for at least twice as long as any of the others—four times in the case of LMNO-P.)
It’s not just you! (And FWIW, it’s actually the rhythm: with the exception of W-X, the last letter of each group is held for at least twice as long as any of the others—four times in the case of LMNO-P.)
Even W-X is no exception, if you count syllable length instead of letter length.