Leg Locks & Knee Injuries, Better BJJ Skills & Wrestlers Teaching Jiu-jitsu

Do you train leg locks? Is there a greater chance of injury if you play with the fire that is the Leg lock game? If you need your knees intact to feed your family is it worth the risk of an ACL reconstruction?
As a white belt in BJJ what is the best way to expand your skills? There are so many different options to study the game and the boys breakdown what they prefer.
If you are a wrestler, ex-pro MMA fighter and now a Jiu Jitsu white Belt wrecking havoc tapping senior belts by the dozen- should you be teaching? People are asking how can they be beastly like you- how do you give advice?