Probably is illegal, definitely unethical, rarely necessary, and likely doesn't work all that often anyway.
Here's a prior discussion from 2009 on some of the so called "secret tricks" stuff : http://www.crappie.com/crappie/main-...-tactic-3.html
And a follow-up thread concerning "ballooning" a fish to follow it back to the school : http://www.crappie.com/crappie/main-...fishing-2.html