Andy: Congressional is an experience that should not be missed but enjoyable is a tougher question. The Blue course is usually very soft because the members want it really green so you have to accept the best tees for your game and the rough is usually thicker and longer than what most people are used to. I haven't found many options when playing the course so strategy is limited. I guess my best summary would be another big parkland US Open course that will really impress your guests.
Thanks Jerry. As you say, I would not decline an invitation but you have diplomatically stated it well.