Yes, I agree, the American ships were not pretty with their furnishings but it was more useful. Why were the rest of the world's ships not like that? The Canadian Forts I sailed in had nicely polished wooden furnishings but, if you wanted to use the sink provided, you had to fill it with a bucket and put a bucket underneath to catch it afterwards. T2s had shower, sink and toilet.
I must confess that I would have to check the textbook to learn of what registered tonnage consisted! We. always, used dwt, didn't we?