Post-Keynesians Don't Understand Economics or Coca Cola

See part 2 here: https://youtu.be/wWzwBpNIDik

I had a debate with some post-Keynesians recently and it was bewildering to see how much basic economic theory they deny.

Sources:

Simon Hall, Mark Walsh and Anthony Yates, 'Are UK Companies' Prices Sticky?', Oxford Economic Papers, 52:3 (Jul., 2000), 425-446: https://www.jstor.org/stable/3488636.

Twitter of Lord Keynes 2: https://twitter.com/Lord_Keynes2

Blog of Lord Keynes 2: http://socialdemocracy21stcentury.blogspot.com/

UK retail sales data from: https://www.statista.com/

Tetley price reduction in 2015: https://www.msn.com/en-gb/news/other/supermarkets-slash-prices-on-thousands-of-items/ar-AA8RqyC

Macleans in 2015: https://www.dailymail.co.uk/news/article-3174044/Toothpastes-costs-just-99p-just-good-brands-despite-3-cheaper-research-finds.html

Macleans now: https://www.superdrug.com/Macleans/Macleans-White-and-Shine-Toothpaste-100ml/p/125695

Price of Charles Worthington women's shampoo in 2013: https://www.dailymail.co.uk/femail/article-2121694/Beauty-confidential-Anti-age-hair-tips-Charles-Worthington.html

Reasons for Coca Cola price fix: https://www.npr.org/sections/money/2012/11/15/165143816/why-coke-cost-a-nickel-for-70-years

Data on Coca Cola: https://www.gurufocus.com/news/169784/the-cocacola-company-19201924

https://www.gurufocus.com/news/169848/the-cocacola-company-19251929

https://www.gurufocus.com/news/170243/the-cocacola-company-19301934