Calfs are notoriously difficult to develop in terms of volume because their shape and volume are mostly genetically determined. I'd like to know if this is also the case for the neck: is a powerful neck largely genetic or can a man with an average neck actually develop a thick neck? I can't find any before/after photos for the neck anywhere online which makes me ask that question.
Genetics plays a part, sure, but a man with an average neck can surely develop a thick muscular neck.
I saw this first hand during the time I played rugby. My fellow team mates used to do 3 sets of 3 different exercises specifically aimed for the trapezius and neck muscles every two days! I assure you that you will gain a significant amount of neck thickness withing a few months.
Another example is seen in the sport of boxing where neck muscles are of utmost importance. In the lower divisions, some boxers have a very thick neck compared to other muscles.
There's some truth to the "calves are genetic" argument, but your genetics impact muscle development across your body so it's not specific to your calves. Your biceps could be loaded with slow twitch fibers as well, as an example. Further, there's a surprising correlation to people making excuses about their calves and people who don't do cleans.
Anecdotally I've found that necks tend to look and get bigger with three exercises:
- A properly performed powerlifter-esque bench press, with your head actively-barely-touching the mat, which requires your neck to be very engaged.
- The deadlift.
- The clean.
All three of those exercises above directly involve the largest muscles in your neck in a safe way. Plus, they're great for a bunch of other things as well. Simply put, you're not going to be deadlifting 500 pounds, benching 315, or cleaning 225 and have a skinny neck.
Genetics definitely play a huge role - you seldom see someone who does not train with ripped 18" arms. However, you do often see people who look untrained or very lightly train with absolutely huge, ripped necks (e.g., Henry Rollins).
FWIW, in going from untrained to benching 365 and deadlifting 515 over the course of about 20 years, I put about an inch on my previously 16" neck. Good luck.