I was part of a shop that did the Pivotal Way and we had Inceptions where the PM, engineers, and a tester or two would be sequestered in a conference room for the day to bang out task lists that went into mid-level fidelity. Technical considerations were debated and sometimes in a heated way, but we never got into implementation—just structure and flow to ensure it jives.

…this reeeeaaaallllyyyy feels like that