Obviously a reviewer will have the hindsight of what happened. However, they should put that aside and when doing a retro review, limit the expectation of analysis and data to what was available at the time.
Being neutral when doing a review is not easy, but once one sets certain paramaters , is not that hard either. What information was avail at the time, and if the market was changing, or in a grey area, what was the most relevant data to subject ?
If an OA marked market stable when the change hadn't hit yet as far as sales prices ( prices often lag behind ltrends), then what were the listings at the time? And what were the marketing times of solds and relevant listings?
It can be excused that an appraiser still marked stable when prices were not yet caught up with trends, but if the same appraiser marked 3-6 months marketing time, when it is plain to see that relevant listings had marketing times of 8 months and above and the solds were showing longer and longer marketing times, then the appraiser clearly marked a box contrary to the data available at the time.
Go step by step through a report, and a picture emerges of how often and in what instances an appraiser reported conditions or conclusions contrary to readily avail data (if that is what they did).