wizzstick:
The table below shows the vowel points of Yehovah and Adonay,
You keep dwelling on the Masoretic tradition, and I repeat myself that this was a late development in the text. Josephus predates that by almost a millennium.
Besides how do you explain that in many texts the tetragrammaton only has a schewa and a qamats? The holam vowel does not appear in thousands of instances among the four consonants. This is thought to correspond to a redaction on the usage of ADONAY's vowels and pointed to a more accurately Hebrew term, which although pronounceable was substituted by SHEMA (meaning "the Name").
The pointing of this redaction lacks the holam, thus rendering it as YEH-HOO-AHH.
In Latin, Martin the monk, used IEHOVAH because the Latin I sounded like our English Y, later the initial I became a J since the consonantal I came to be written as J.
He also wrote V because in Latin V was both a vowel sound like OO and a consonant sound like W, it wasn't pronounced as V in English back then in Latin. In later pronunciation changes the consonantal V (W sound) became what we pronounce as V in English, this change has happened in many languages like in German and Dutch where the W is a V sound, and even in modern Hebrew the letter Waw has come to be Vav.
Today's Jehovah comes from IEHOVA(H) in Latin from Hebrew YHWH (JHVH). The research supports that using Jehovah is as good as using Yahweh. They are merely English translations for the Divine Name which could be more credibly pronounced in Ancient Hebrew as YEH-HOO-AHH.