That's good advice. Someone with a degree in plant biology can pass the ISA test on the first try and then they are a "certified" arborist. In my opinion, to be a true arborist is someone with knowledge and experience. A doctor, nurse, or paramedic needs hands-on training before they can be called a doctor, nurse, or paramedic. I was the latter and I had an almost 2 year program with nearly 6 weeks of field work before I could be called a paramedic and even then, when I the new guy, I still had a whole lot to learn and was paired with someone more experienced. Read, read, read and ask a lot of questions but there is no substitute for being in the field just make sure you practice Good Habits and don't hone skills that can cause harm or injury.