This post is for trainee arborists/climbers, just a few thoughts for you to consider......
It could be argued that none of the people in these videos should be involved in treework.
Why did none of the trainees have the mental strength to stand up to the instructors? Some of those trainees knew instinctively that what they were doing was wrong, were they too mentally weak to say anything? As a climber you have to go with your instincts, if you feel something is morbidly unsafe it's probably just 100,000 years of human evolution trying to tell you something very important, it's how your ancestors survived and how you got here today.
From my experience in the industry you can't always trust instructors, bosses or crew leaders to tell you what they think is going to happen, you have to learn to think for yourself and have the strength of mind to go with your own instinct. If you think something is wrong on the job, then stop before you kill yourself or someone else. If you think something is inherently unsafe despite being told by a boss or co-worker 'it's fine, just go with it' then stop and find another safer way to do it, even if it takes a bit longer.
I've worked with so called experts, bosses and instructors, assessors (NPTC/LANTRA/FASTco etc) who have been found out on the jobsite for their lack of experience/skills/knowledge in certain areas. Some of them have a lack of common sense. These guys dont know everything and the most humble of them will readily admit that. None of us know everything in treework and if someone acts like they do, don't trust them, there's a fine line between confidence and arrogance.
When you become a climber, you need to have the right mental state. If you dont think you can stand up to people when its your life on the line, then maybe you should consider finding another job.
Roughly speaking climbing and working in trees is 20% instruction/book knowledge, 40% experience and 40% mental. You get the basics from instructors, thats it. You dont get experience from instructors. Their experience is not transferrable to your mind, you make your own experience and this relies on your natural attributes - both physical and most importantly...mental.
Assess the level of risk in your mind, regardless of what an 'instructor' or 'boss' might say. By all means ask for other people's thoughts or opinions - but you have to learn to be responsible for your decisions in the tree. Look at what's happening, look at the bigger picture, think of the outcome of your actions.....understand timber, weights, forces, tension and distances because when it comes to rigging trees down these are some of the most important factors.
Most bosses/instructors in treework respect strong minded trainees or apprentices, just remember in most cases you have to work with them not against them. Tree work can be a dangerous job at times, it's impossible to remove the risk of death or injury but sometimes by not speaking up you increase the risk.