Why is macroeconomics so hard to teach?

Summary:
Doesn't seem hard to me you just choose which Theory you fancy and then just teach that Theory.... MMT or otherwise... then let the dialectical process sort it out... Art Degree methodology 101... What is so hard about that?  I don't see it.. Macroeconomic theorists disagree on almost everything. That is one of the reasons it is such a hard subject to teach https://t.co/C5q0TyTuQv — The Economist (@TheEconomist) November 17, 2018

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