My personnal opinion on gyno is that it is definitely different in every person. How prone you are to it is genetic. To the best of my knowledge, it is the actual estrogen working in your body. Whether it be your levels of estrogen actually rising or an anabolic substance that you are introducing into your body peripherally converting to estrogen. Most gear will cause your nuts to shrink. When you reach your cycles end, that is why you would take Clomid, to help them return to full size and function. You can take anti-estrogens to help not only the gyno but, also to keep water off and I feel more stable with them. However, these substances can cause decreased results from your cycle. Some people believe that the estrogen helps to clear the receptor sites so that test and its derivatives can function within. I personally get sore nipples everytime I peek in my cycle. This goes away when I am off and normally stays away. On that note, I would not consider it a light issue. Most of us lift and use gear to look better and feel better about ourselves. I wouldn't feel comfortable taking off my shirt to see a set of A-cups on top of my 52 inch chest. I would rather be safe then sorry. If the anti-estrogens decrease results, that is just one more cycle you get to plan and research. That is the real fun of it all anyway. I hope this helps.