I know some states do not require irrigation license and others do. Mine does, Texas, and also if you have employees that you want to leave on site, send unattended on service calls, multiple installs, ect..... then they must have a irrigation tech license.
I have stated before that our course and test is for the technical side but really no "real world experiance".
Some have said they feel you should have to apprentice under someone for a few years. I agree somewhat but not entirely.
Some of the negatives
I would have not been able to do this while running my own landscape business.
Most all the "irrigators", even the "old timers" in my area, I would really not want teaching.
I would rather the course have both classroom and field training. I know Texas A&M has the extension Texas Agri-Life with locations throughout the state. The one in Dallas is large enough that they could have field training.
What are some of y'all [Texas slang] thoughts.