I probably should have chosen a better title...something like "The possible dangers of the inexperienced teaching the less experienced". After all, we're all students...every day of our lives...
That said, some might ask, "Why is that (or could that be) a problem?"
Playing the DB is quite complicated and physical...and believe it or not, potentially "dangerous". You can actually cause injury to yourself...permanent physical injury if you play incorrectly. It's not going to happen after a day or two, or even a few weeks mind you- but Carpal Tunnel syndrome and other muscle and tendon related injuries are born of poor technique, and can render you unable to play for long periods of time.
Improper technique can also stall forward progress. While some gains may seem to be achieved, a "wall" will inevitably be hit where further development is impossible without a complete "overhaul" of the players approach.
There is also the problem of having to "unlearn" poor technique that has been ingrained...arduous and unnecessary!
I'm sure that no one would willingly pass on bad information, but the word "ignorant" means that one quite literally doesn't know...and if one doesn't realize that their approach is not sound, they may continue unwittingly along until they encounter one or more of the issues listed above...and there are more than I have intimated, believe me!
More to come...
Joe