Why I consider the Linear B syllabary to be a streamlined refinement of the Linear A syllabary and not a new syllabary:

Keyboard assignments Linear A:

Note that this verifies that the Linear A syllabary has at least 49 syllabograms and homophones in common with Linear B.

Keyboard assignments Linear B:

Note that this verifies that the Linear B syllabary has at least 49 syllabograms and homophones in common with Linear A. Since the Linear B table of syllabograms contains 49 syllabograms and homophones in common with Linear A out of a total of 67, the total percentage of Linear A syllabograms and homophones in common with Linear B = 49/67 or 73 %. This percentage is high enough to justify the hypothesis that the Linear B syllabary is a direct descendant of Linear A, such that for all intents and purposes, the base syllabary plus a few homophones of both is close to equivalent in both syllabaries. This is why I consider the two syllabaries actually to be one, with Linear B a refinement of Linear A. We note in particular the the syllabogram WE was added to Linear A just before that syllabary was abandoned in favour of the newer streamlined Linear B syllabary. We also note that Linear B abandoned scores of ideograms and a few numeric syllabograms in Linear A, which are themselves indecipherable, because we do not know their phonetic values. This makes them irrelevant to the Linear B syllabary.

The implications of this hypothesis for the decipherment of Linear A are highly significant.