"You can either accept the premise that we have a century's-worth of data, and finance experts in the article provided say the correlation is statistically significant (meaning progressive policies are better on average, for the economy)"
wrong. They have not shown ANYTHING to indicate that it is the policies that caused the market performance. They simply pulled the DOW performance while Dems and Reps controlled the White House. That DOES NOT SHOW that the President was able to control the market. You have not provided ANYTHING to show that the President is able to control the market on his own.
"Or, you can conclude that, for 100 years, Democrats just got "lucky"...over, and over, and over, and over again. "
Or I can conclude as I already have that it is a bunch of bullshit to assign market performance in such a simplistic manner. To many factors are ignored to make it have any worth. but again... follow along like the good little sheep.... perhaps it helps you sleep better at night.