Crane training

My boss is thinking of buying a crane and training me to operate it as I’m the company hiab driver.
He seems to reckon I would only need 3 days training which I’m finding difficult to comprehend.
I’ve googled training companies and they all seem different.
Does anyone have any recent first hand experience of training?

I don’t think crane training can be done in 3 days. It seems one of those jobs that like abnormal loads, many can do - but it’s knowing how to react when the ■■■■ hits the fan. That’s why it’s one of those jobs where you start at the bottom and learn the trade over many years.
You have to be pretty good at maths too I would have thought.