Ken Schwaber and Jeff Sutherland are two of the creators of the Scrum, and co-authors of The Scrum Guide. They are also part of the group of authors of the Agile Manifesto.
They both criticise SAFe, as detailed later in the document.
Jeff Sutherland in particular says that SAFe is inconsistent with the Scrum guide and codifies dysfunctions that can cripple teams for years.
Ken Schwaber says that there is a fundamental philosophical schism between Scrum and SAFe because Scrum controls risk through empiricism while SAFe tries to control risk through predictability.
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