ACA: ExportToAutoCAD - Room Tag Attributes Not Shown

I came across something curious today. Someone wanted to link an AutoCAD^® Architecture drawing in Revit, but the Room Tags were not showing. That is because Revit cannot read AEC Objects (not the curious thing). I suggested using one of the EXPORTTOAUTOCAD commands to create a copy of the file, with all of the AEC Objects exploded to AutoCAD linework. That was done, but in the resulting file, the blocks that were the result of exploding the Room Tags were not showing any of the attributes that should have been displaying the room name and number.

Here is the curious part: Grips for the "missing" attributes displayed, and, in the Properties palette, values for the room name and number attributes were shown.

I tried REGENerating the drawing, I checked layers 0 and Defpoints to verify they were on and thawed and even tried an OBJRELUPDATE (even though the object was now an AutoCAD block, and not an AutoCAD Architecture Multi-View Block). I inserted a new instance of the block, and values entered into the room name and room number attributes displayed as expected. Fortunately, lunch intervened, allowing my frustration to subside. With a semi-fresh brain, I returned to the issue after lunch, and it occurred to me to try running ATTSYNC on the block. And that turned out to be the solution, as the values displayed after doing so.

I was not able to reproduce this in a sample file, created with the same content, but at least I have a solution should I come across this again in the future.