Regarding the Underarm Turns. I believe they were in use in the USA first. I always was under the impression that move was stolen from one of one of the other USA styles. Being a bit old fashioned I would rather see the Opening Out Right to Left, or the Rope Spin from an Alemana which is what Laird suggests. It is a beautifull step when done correctly, and is a perfect lead into many other moves.

Pretty much all the foundation work ( and many other variations ) have been adapted from the Amer. style syllabus, which in turn has revamped most of its content in Sq. Rumba, Cha Cha, Mambo/Salsa, from the Bolero and Swing genres .

And even they are extentions of other more indigenous dances .

All dances done socially and in comp. are hybrids. The 2 that are closer to their originals in Latin.. merengue and bachata, and even they have added many variations that were not in the original format... Intern. Rumba is tied loosely to Bolero ( its template )..

Terence. Its worth it to Google. George Raft Bolero. From the 1934 film of the same name. Starring George Raft and Carol Lombard.

Have seen it several times ....the movie, that is..and also with Veloz and Yolanda .. there are several other versions in movies, but all are more in the modern dance style, and dont truly reflect what Cubanos dance of that ( or this ) era..

I doubt that the derivation is from 'a la main'.
Allemande is French for German.
Alemana is Spanish for German.
The Allemande was a dance of the 16th century which originated (surprise) in Germany and became popular in France.

One should remember that the names given to mnay of the variations in both Standard and latin were " corruptions " , descriptive, and just plain made up..