I have read here a million times that after you come off cycle, you lose your gains or something to that effect. I kept all my gains and continued to grow post cycle.
Granted: I did my cycle when I was relatively out of shape and nowhere near my genetic potential, but as for gains, I kept them all. I did eleven weeks of 500mg/wk of test-e and kicked it with 30mg dbol for the first 4 weeks. I went from 189 with 23% body fat to 210-215 at 16% Body fat at the peak of my cycle: about week 12. Bench went to 250, Real squat to 350 and Deadlift to 405. Today, I am about two months off of pct and am back to around 190lb HOWEVER, I still have my lifts and have moved up on deads and squats.
I guess that when people are talking about gains, they mean hypertrophy, not strength. Contrary to the CV on this board (for which I have a great respect), a novice cycle for a 30 something, kinda out of shape guy, will do wonders assuming that he is motivated to get to the gym. While I wasn't able to keep my swolled up look, I am lean and strong post cycle and do not think I could have kept the extreme motivation without the gear.
My hypothesis: If you are out of shape (within reason), a mild cycle may be just the ticket to turning back the clock a few years.