John Sells was simply describing that the more modern versions of 54 used a standing backfist.
As I would characterize it, the version used in Matsumura Seito (I have a copy of Tosheki Gillespie's Panther video doing the form and some apps.), and those from Kyan (ie. Seibukan, Chiniba, Matsubayshi and others) being descendent of Matsumura do the drop to the floor.
Those lineages from Itsou (Mabuni's Shito ryu and Shotokan) use the standing backfist. I guess his implication is those are 'newer' than the other versions. But how to 'prove' it I don't know.
Any of the answers have uses, it's just they're different ones.
Gillespie shows the opening technique blocking a kick and then rising.
The version of Gojushiho I practice (from Tristan Sutrisno) is related to the Matsumura/Kyan versions, but his Shotokan also has Gojushiho Dai and Gojushiho Sho.
I never went far enough with him to learn his 'bunkai' for the kata. And I have more than enough toys to play with, but his versions, a variation on the 54 theme, has other uses, and I work it specifically for the advanced breathing and energy release that is used in his practice. But that's another topic.
BTW, I only did some quick research picking up some Gojushiho examples. I'm rarely satisfied with the eye candy which is avaiable to look at. IMO, in most instances a great deal is being held back from even all out performance.
But they are useful for discussion, and of course anyone who really has a question can google them out for themself for initial research too.
I often wonder why more don't begin by looking at what's available themselves. Our discussions are fun, but they're hardly authorative as we really don't know each other.
bushi no te isshinryu
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