Well to answer you question, yes. Yes they can. The abuse of very powerfull androgens especially very high doses of testosterones, nondrolones and the likes of Anadroll 50 etc, can permanently affect the feedback loop and your pituitary gland, hence you will never achieve normall test levels and they will always be depressed. This is a fact. Ofcourse for this type of damage to occur you need a long time if ABUSE of the before montioned compounds. The problem can get so bad that not even HCG or Clomid can premanently "fix" you.