Hi, if Frank is asking about the expected rule of engagement for editing, then perhaps this longer answer will help and this is a good way to go over it for people who may be not familiar with it.
When collaborating on Google docs, there are three modes:
1. open editing: this will immediately replace existing text as is and is usually used on something that you deem non-controversial, information updates, obvious mistakes, editorial, etc
2. Suggestion: this puts in cross-overs on previous text and waits for someone to approve the change text, reserved for something that may be controversial
3. commenting: this opens a text box on the side for discussion: reserved for things that are definitely controversial
You can change the first 2 mode easily but the default is set by the owner and is usually open editing, unless changed.
Either way, you can see the old versions and the changes from the first pull down menu.