Never put much weight on it, just stating the fact you're never 100% natural after a cycle.. whether it is for the better or worse.
Since your initial claim of 50lbs of lean mass you've added "perhaps 35lbs of it is lean muscle", "muscle memory, stopped smoking, change of diet" which makes things more believable. Just now admit that a large portion of the 50lbs was fat and fluids and you're getting closer to the truth. It's still impressive but don't kid yourself.
Yeah, like I stated, probably 35lbs of lean mass. One cycle doesn't change your physique 15 years down the road. Especially, if you keep none of the gains. Whether someone calls it natural/clean, is irrelevant.
I was at most 12% bf. On 200lbs, 24lbs fat. From 150lbs @ 7%bf, 10lbs fat. So, 140lbs dry to 176lbs dry. Yeah, 35lbs lean mass is about accurate there.
If the diet were the same and I only just started lifting, there's no way I'd increase that amount. Tripling your caloric intake, meal frequency, you can make a big change.