When publishing a service with feature access, you cannot include any tables that include computed columns.
In our case, I wanted to calculate the latitude/longitude from the SHAPE column by using the SQL geometry functions. In this instance, Latitude and Longitude would be dynamically calculated from the feature's geometry and stored in their respective fields.
Another case, could be for creating unique ID's from a predefined ID system.
Or for concatenating objects.
Or for creating time differences.
Etc.
I feel that this enhancement would greatly improve data and the ease at which data is created and can then be shared. This would be especially powerful when utilizing mobile data collection techniques, so that reports could be greated dynamically, without having to go back to the office to process additional data by calculating fields in GIS.