I remember when the 1004mc came online. When first introduced there were no available apps for automating the grid. People were fretting about the length of time it would take to manually run multiple queries and how you couldn't even do a median of sale/list instead of the median sale / median list. Because it had never come up before for them, many appraisers didn't even know what the difference was between the average vs the median.
Some of the appraisalware vendors responded by building apps that they intended to sell to appraisers as an extra module, but a few appraisers (including me) developed Excel-based worksheets that could accurately populate the entire grid with a single MLS query/export, and then we offered the distribution as freeware so that appraisers didn't have to pay a dime extra to do it. IIRC my freeware distribution had ~15,000 downloads all by itself. (I wasn't even doing GSE appraisals and never had use for the worksheet. I just did it because appraisers had no money to be buying these from the appraisalware vendors and because they were stressed.)
So by the time the 1004mc became required, there were several apps available (a couple were free). Everyone had access to apps that would populate the grid using a 3minute process. I could hit "results" on an MLS query, mark/export the results into an .xls file format and copy/paste those results into the worksheet in 3min or less. My worksheet even included the 1004mc form itself. Just fill the rest of the form out and print to a pdf or copy/paste into an xml addendum.
The point being, whatever requirements they can come up with I am confident that most appraisers are capable of learning what they need to learn in order to meet those expectations. I saw the group do it - albeit on a narrower scale - in a matter of weeks. I am confident the appraisalware vendors will eventually refine their apps so that they'll be easy to use.