Matt, you are wrong.
There was a hormone replacement study (I don't remember what journal so can't look it up) that was double blind and randomized (gold standard) which looked at the effects of hormone replacement and exercise.
One group exercised and given a placebo shot
Second group given testosterone without exercise
Third group exercised plus the testosterone replacement.
In short, the group that was given test, but didn't exercise, gained a small amount of lean mass and lost a small amount of bodyfat. The group that exercised and given test replacement had several times the gain of the test without exercise group.
So, yes AAS can build some lean muscle without exercise but it is a fraction of what can be built with combining the two. Weight training is essential in building muscle, the AAS just makes it easier with better recovery. Proper nutrition and proper training makes using AAS much more effective. Then there are individual variations in responses to AAS but I don't believe there have been too many studies on that.