Here are two serious questions:
1) As a provider of a framework whose intent to increase the ability of an organization to deliver value more quickly, why would you put limits on what could be in your framework? This means limits on both what could be added to the framework or what could be substituted for any of the frameworks rules, roles, practices and events? If you do, you are limiting the effectiveness of the framework.
2) As an adopter of a framework with the intent to increase your organization’s ability to deliver value more quickly, why would you accept limits by the framework you wanted to use? In other words, if something was more effective than what was in the framework, you’d have to stop using the framework to adopt the practice, … Why wouldn’t you find a framework that didn’t require this?
As far as I can tell, the only real acceptable answers are:
1) I don’t know how to do otherwise
2) I don’t know of a framework that doesn’t do that
Let me know if you have other answers.