I am not sure how many of those differences are statistically significant, but if there are significant differences, I would speculate that the reason may be that the PDO is more closely connected with the canonical Pacific-North American (PNA) pattern. ENSO forces a similar pattern that maps onto the PNA, but it's not quite the classic PNA. As Michelle's post showed, the PNA has a strong influence on precipitation in the Tennessee and Kentucky region. Again, this is speculation, so this idea would have to be tested before it could be trusted.