I did it one time and found they did toss in a few very esoteric questions on matters which I had never encountered before and took a good while to find the right answer for. The one I remember had to do with the hydrodynamics of a turning circle and I finally found the answer to it in Robert Zubaly’s book titled “Applied Naval Architecture” which at that time (1998) was not one of the USCG’s standard references.
Just an imo, but that is an excellent work on Naval Architecture btw and well worth any maritime professional having in his or hers library.