unfortunately the math is not always all that simple.. if OPs maintenance calories is 2000 and he is eating 3000 cals trying to bulk up and he is stuck at 164 pounds , then simply bumping the calories up to say 4000 per day is possibly just going to make him a 164 pound guy that craps 5 times per day instead of the one time per day he does at maintenance cals.
he needs to better assimilate and partition the calories he is already eating in order to gain muscles. not just throw more cals in (which can actually cause more harm then good).
he needs to absorb and assimilate his nutrients better, he needs to better partition these nutrients towards muscle building, he needs the capacity to be able to store a whole bunch more glycogen then he is capable now , he needs to be able to super compensate the storage of minerals and other nutrients intercellularly, he needs to retain a lot more nitrogen and upregulate protein synthesis, he needs more blood volume, he needs more water and electrolyte retention, etc. etc.. If he is already eating in a surplus he needs all these things, not more cals.
and guess what the good news is. all these things are possible. he just needs to take the right drugs/steroids and all those magic switches I mentioned above will be turned on
yes. sometimes it is as easy as adding in the right drugs to your diet and training, and not always the diet and training itself that needs change.
we are often times so quick to jump on guys diet and training and say theres problems with it , when they may just need the right drugs and synergy between all these things