Our organization is at CMMI Level 2, and as part of the requirements of the level, we have to maintain an RTM which more or less contains the following entries for each requirement:

• Requirement Description
• Reference Section Functional Specification Document
• Reference Section Design Document
• Reference Section Test Cases Document

Now, this might be an overkill for a small project. But more importantly, this could be a nightmare to maintain when the requirements/ features keep changing, and documents have to be constantly updated.

What do the gurus say about this? Should one avoid such level of documentation or are there any tools to manage when a "change" out dates so many artifacts? And by using the term 'gurus', I am not talking of coding champs; rather people like Steve McConnel or others who have worked on commercial projects of medium to large scale.

Quotes/ book references/ articles will suit me.

EDIT: It's not just requirements that change. Design Document can change; well, even test cases may change.