Late to the party.
Email conversations with reviewers while they are working on a report are common in many areas outside of the residential lending world. It used to be phone calls, but now it is almost always by email (I'm not sure which I prefer - I can see advantages to either). The reviewer is typically looking for the appraiser to clarify something or consider something else to see if what they are reading makes sense or is credible. Most of the time, some additional discussion is enough and if there aren't any actual corrections needed, the reviewer can add the notes to their review and "certify" the report (for lack of a better term). It isn't the most fun part of my appraisal world, but almost everything I produce gets reviewed and depending on the reviewer I may have to clarify something that is a big deal, even doing a new report with a different value if I screw the pooch (I have - in fact I had to change my opinion of value on a report just this fall when I missed something). Or, more likely, it is just clarifying something I should have explained/documented better or something that, frankly, a reviewer should have understood (IMO). It is the least fun part of the job whether or not it is reasonable, but it is definitely part of the gig.
FTR - the email exchanges are not in place of doing the review and presenting it to the client. They are part of the process of doing the review. They are gathering data which includes asking questions about parts of the report that may not seem clear. When they are done with their process, they then send the actual review to the client. The review includes corrections or items discussed with the appraiser. That is the actual report - not the emails. The emails are simply part of the process in many worlds.
And, yes, personalities can sometimes get involved on both ends. I know there have been reviewers who made me cringe every time I see a note from them and there are no doubt appraisers (hopefully not me, but I cannot guarantee that) who make a reviewer cringe when they see it is one of mine they are reviewing. But, since the review process is there to make sure the report is reasonably concluded and supported, they do need to contact you if they have questions and the blind review process wouldn't work very well (particularly since it is narrative and everyone has their own style, anyway).
