doing little bicep work may not work for you but I have heard bodybuilders with 20" arms (and lean) who don't curl.
Plus look at the big lean powerlifters who don't curl much or at all and none have massively undeveloped biceps.
No disrespect man but you should realise we are all different and what some people swear by doesn't do shit for others
P.S I wish I could do loads of chins like Steve and SL... I suck at them lol
you are taking the elite power lifters and comparing them to the average gym junkie...doesnt work that way.
Besides, most of these guys do assistance work anyways.
Also, if they curled, they would have BIGGER arms
There are guys who arm wrestle with me who have 24" arms dude...you wont get that by deadlifting.
Look at your body man, you got a pretty big back for someone your age, but you have small arms...start curling. They will grow IMO