There is telling the truth and being an ass. You might be saying the same thing but often it is HOW you say something.
While many of you are fantastic at bonsai you are missing the point regarding how you communicate with others.
The other fact regarding when Harry grew up is, if you were an ass, you got your teeth bashed in. This made for significantly more polite people then and would still work today. In today's world we seldom settle things the old fashioned way.
As someone who has been a coach since the late 80's you don't teach, mold, or motivate by telling one of your basketball players, "your shot sucks" or one of your football players, "your tackling form is junk". This is not called being truthful it is called being an ass.
Wave your flag and toot your horn about how right you are to act this way all day long but it does not make you correct. It certainly does not make you a teacher.
While I do not believe that every tree can be a bonsai, what is important to ascertain (even guide a person to understand )when "helping" is the goal for a particular tree.
For me, many of my trees are merely to learn the basics of potting, pruning, shaping, and overall the horticultural skills necessary to be good at bonsai. Why would I practice on a $500 or more piece of stock when it is quite likely I will kill it? That is simply retarded.
Now the advice should be, "If you want to develop (or purchase for your collection) a "showable" bonsai, here are the best practices to achieve that goal." Part of the "best practices" would be to obtain the best stock possible and to realize that not doing this basic step will likely limit your success long term.
For example, becoming a good shooter in basketball requires a specific, detailed skill set and MUCH practice. If a person will not do these things, they will limit their success in basketball. It is a fundamental. Are there successful shooters with bad form? Yes but they are the very rare exception.
I could teach any of you to be a good shooter if you would allow me to make subtle changes to your form and to encourage your progress. I would not be successful teaching you by telling you that you suck.