The increased fees efficiency of AAS is a proven concept, that's why they use tren in cattle.
But other than that, (or in addition)
my take is that when you train and use AAS you have an increased metabolism due to always repairing and building muscle tissue (increased protein synthesis), so I would think that one wouldn't need much of a calorie deficit to lose fat, if the TDEE is calculated according to when one is not on AAS.
I might be wrong about this though,
but I know it's definitely possible to both lose fat and gain muscle when using AAS and eating correctly.
Last summer I did lose BF and all I did was to stop force feeding myself, so I ate less, but I doubt I had a calorie deficit as such,
but I did do a lot of walking, probably 1-3hours each day.
And a lot of outdoors sex, trying to find monuments and landmarks and such,
so I was very active. It was a good summer if I concentrate on the good stuff.

I think I drifted off a bit there....