to answer your question.. yes..
However you missed my point.. if I was strictly teaching someone to cast I would deffinetly teach them switch casting then progress to the other casts. However on a guide trip people pay 300 bucks to fish not learn to cast. and good or bad like it or not people take more guide trips than they do casting lessons therefore the guide has to teach them to cast while they are fishing. you cannot fish steelhead with switch casts..
Also here in the states in the summer ( when most guide trips are taken) the fishing is best at first light to you gotta get people casting 50 feet within a few minutes so they don't burn away the best part of the day learning how to cast... Therefore I would not teach the switch cast.
as much as i dispise the cast the first thing i teach is the snap t then the double spey on the other side of the river. on a guide trip thats all you can do.. In a perfect world people would learn to spey cast before taking a trip but this is the real world and they don't thats just the way it is..