Yup, thick veiny forearms and neck really distinguish you as a gymrat when you have on a shirt.
I used to have easy growing upperarms. At some point i looked in the mirror and thought Geeez...with them relatively tiny forearms it just looks like baseball bat, so i started working them out with burning desire and this is where I developed my OCFB Obsessive compulserary forearm behaviour......
Every other day... and it allows me to train biceps only 1 * every 7-8 days as serious forearms training keep biceps full.
i like to shred them mofos with high volume:
7-5-10-10 reps hammer curl
7-5-10-10 reps reverse barbell curl
10-10-10-10 reps reverse grip cable curl
8 * 15 barbell wrist curl
8 * 15 dumbell wrist curl
I really like the improvements in gripstrength for my back workouts too!