The GML Simple Features profile is recommended for use with ArcGIS and is the basis for WFS support in ArcGIS.
Is there an easy way to determine whether a particular WFS is encoding using that or an alternative profile - perhaps by looking at its GetCapabilities?
I am keen to know this so that, if/when I am unable to connect to a third party (or Esri) WFS via Data Interoperability, or if the WFS To Feature Class tool blows up ArcMap, I can start to understand why that may be the case.