All arachidonic acid is is an omega-6 fatty acid. It is found in beef, pork, eggs, thats why when people eat a lot of red meat one of the reasons along with many other of the benefits red meat has on muscle is the increased arachidonic acid.
Supplementing with arachidonic acid just brings the levels up higher. and that is why it most likely says to take at least a two month break after using it because too much arachidonic acid is not good for your body(inflammation, if you have bad joints can make them horrible joints)
so yes it is good for muscle growth however not so good for other functions of the body. So balance out of it is important for yourself.I personally just like to eat a lot of red meat while training intensely.
the opposite of arachidonic acid is fish oil which decreases inflammation and does the exact opposite of aa effects.
Does that mean you stop taking fish oil year year? No way
some times Ill take in 12 grams fish oil and sometimes Ill cut it back to 6. I cycle how much fish oil i take.
arachidonic acid is a good natural muscle builder and if you can handle it go for it. I started it one time my joints just could not take it.