Thanks, Azizi

I agree, there's definitely something to do with motion to "stormalong," like "get along." The phrase "walkalong" (often spelled as one word) is also very very common in chanteys. I really don't know, but if I had to guess though I'd say that that 'poetic' aspect was something that was played with due to the sound of the name. In other words, the name (say for argument, "Shango") came first, and as it sounded like an " X along", with the very poetic "stormy" aspect, it became the subject of verbal play. The most striking chorus is the one "come along, get along, stormy along, John." Anyways, all just speculation.

"John" is also very generic for any random "sailor" (and to some extent, any random "man") so that one is probably a less fruitful line of inquiry.

Funny also the preponderance of "long", i.e. Lucy- / Storma-