Ive found strength to be the most reliable indicator and method of keeping gains.
Ive never been one of those guys that is satisfied to "stimulate" and "feel" the muscle and all that jazz. That works for alot of guys, it doesn't work for me.
For as long as I have been working out I simply try to workout heavier, end of story.
Sure there maybe more effective ways to grow quicker, but I have my reasons, and I feel they are pretty good ones.
Now that said, I focus only on get stronger on every cycle, I let the diet and the heavier training take care of the growing, but I don't specifically train for strength like most powerlifters would, aka in the lower rep ranges, training for max strength, I try to lift heavier all the time on everything. And this isn't very difficult for me personally, I gain strength fairly easily just straight up and from anabolics in general.
I simply stay in the 5-8 rep range, for 5-3 sets, so my volume is still fairly high. And let the anabolics quickly bring me strength gains.
After I come off cycle, I simply try to keep replicating the same workout, without the benefit of anabolics.
Its difficult, but if you can "force" your body to keep lifting the same routine as on cycle, you will keep almost all of the new muscle.
Your going to lose a rep or two, but fight it tooth and nail, keep the strength levels the same.
I simply use longer rest periods to try to match my on cycle workouts, and it does work.
Logically it makes sense to me atleast, if you built the muscle specifically to lift heavier weights, and even after your androgen levels drop you force it to keep lifting those weights, its going to have to keep that muscle.
I feel that the guys who use anabolics and "stimulate" the muscle and try to feel the contractions and all that, are growing new muscles that don't have a "purpose" in the body.
The anabolics put them in a state that allowed them to pack on alot of muscle, but those muscles dont have a "use", they didn't gain the strength that SHOULD have come with that muscle.
So after cycle, without the anaboilcs, the body simply has no reason to maintain it, and they have no method to force it to maintain it, as they didn't make good use of the gear's ability to produce strength gains. Use strength as the reason for the muscle to be there, not the drugs.
Muscle from strength gains is more important to the body and easier to keep with simple force of will.
That came out kind of rambling, and I didnt really say anything we didnt already know, but I still think it will help alot of guys make sense of the whole "keeping gains problem".