He had never shot better than 38% from 3 or 45% from 2 in 4 seasons at San Diego with career averages of 35% and 42%. He's at 52 and 55 so far this year. He also never had an assist rate higher than his turnover rate (and his highest assist rate was 14.3), but this year he's at 17.3% (close to PG level) assist rate and 16.4% turnover rate. He's been unbelieveable, and nothing in his past play would have predicted this, even if you accounted/adjusted for better scheme and more efficient (non-starring) role in the offense.
He was always more than a spot up shooter, but he stepped up in competition and got a lot better at the same time. Doesn't happen that often.