Some of the processes they use at Manning seem a bit archaic. To send a document to multiple people for review, it's vastly more efficient to use Adobe Acrobat to convert it to the the version of PDF that's enabled for markup using just the free Adobe Reader. You can then put the document on a website or Acrobat.com where everyone is looking at the same instance of the document and, most importantly, everyone can see the previous comments. That way, if one review says something dumb, another reviewer is likely to pick up on it. You can then bring all the comments back into a Word file.