That would switch us back to the 'genuine' Tizona riddle.
In a way, Charlton's setup would be the correct one, if we think of the period the actual episode took place; no blunt ricasso, thus no way to place your fingers but all of them in the actual grip, providing enough (grip) length is applied. Whereas the Tizona (short grip) example as today is brought to us, suggests a ricasso finger grip which only appeared a few centuries later.
Take a look at this XVII century exponential example, in that only three fingers would fit onto the grip, two fingers left to hold the ricasso.
Note that the quillons are welded to the cup bowl rim, and not fixed with interior extensions, the first being a (more) Portuguese way.
... And don't forget to read my suggestions with a pinch of salt; i am only playing by ear
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(picture courtesy of "As Armas e os Barões" de Eduardo Nobre).
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