yes it is. the landed (political) class married off all their daughters to rich business men (middle class) and those peoples children became the upper class. unless you are a rich business man you arnt middle class. unless you own large amount of land you arnt the landed class. if you work, you are working class. its a bit more muddled than that but you get the idea. work = working class. the clue is that the poorest workers don't earn vastly different money to well paid workers.
Ireland