I am a subscriber to Banjo-L in the digest form, but I receive it only sporadically. Sometimes the interval between digests is so long I think my membership has been cancelled. Then it shows up. You still might eventually get a reply.
Your professional picker friends didn't give you the whole story. The idea is tighten the head until it pops, then back off half a turn. That's the correct torque.
As far as I can tell the torque wrench is only for the most anal of bluegrass players. The ones who debate endlessly over the best alloy for tone rings and have memorized lists of Mastertone serial numbers and dates.
I play old time. The tightness of my banjo head is whatever it was the day I bought it. It looks more or less flat to me and sounds fine.
Bye the way, another school suggests tuning the head to a particular pitch rather than a particular torque settings. What pitch? No consensus there.