I'm a guy who would fall squarely into the "safety" side of most arguments regarding my kids.
I NEVER mentioned my interest or that I played HS football to my son instead directing him towards basketball, track and soccer as good alternatives because I know that pretty much everyone that's ever played HS football lives with injuries 20 years later....including me.
However, when he showed a real interest (not just a passing fad) in bikes I got him set up with an MSF course, took it with him and rode with him all the time the first year. We went on several weekend trips in groups where he rode in the middle and could get a good perspective on safety and good riding technique from different perspectives.
People called me crazy, but I'd rather put out a confident, competent rider than an oblivious fool.