The thing is this......deca can create prolactin buildup. Prolactin can result in many unwanted sides as well as a pecker that doesn't work. Prolactin buildup however is in direct relation to its precursor, estrogen build up. The more test you are using the more estrogen conversion. If you keep your test low, estrogen is very very easy to manage and control with an AI which will in turn control prolactin. Your friends method is an old theory that many people will swear by, simply because it is all that they have heard any never tried anything different. You need to do what you are comfortable with, but just remember there is more than one way to skin a cat. Good luck
