Ok Let me quote an example: Suppose you have a test team with 6 test enggineers. And you have any problem in understanding of the module funtionality so you can ask one of the test engg. In Informal reviews you are not required to formally declare with in a team that you have a problem in understanding modules funtionality -you can just go and ask him to clarify it.
every project need to deal with different style according to requirment testing techniqs may be same. Some times these way to working comes with experience and not documents because every one's experience speaks something