cracking any linear a at all represents a totally mindblowing accomplishment imho...
It's likely that one or more of the claimed decipherments is at least partially correct when it comes to Linear A. In "Lost Languages" Robinson suggests that the total sample of Linear A is too small to permit a decipherment. Sir Arthur Evans was certain that Linear B could not be Greek (due to the supposed and erroneous antiquity assigned to that culture) and refused to publish the relatively small body to surviving tablets (Evans lost the first batch of tablets he excavated due to, well, incompetence), dying (1941) before making any headway. Ventris' crack of Linear B (1950) found (tah-dah!) that it was Greek. Blegen's best-first-day-ever at Pylos (1939) had turned up a large archive of Linear B, published it, and broke Evans' grip.