Superdrol is 5a reduced, just like DHT. It has a 2a methyl just like masteron (2a methyl DHT). Its also has a 17a methyl group increasing the bioavailability. So basically it is 2a, 17a dimethyl DHT. The two methyl groups change the shape of the molecule, thus changing the binding of the molecule and the properties of the molecule.
So - i have asked this before in another thread about how TRT will / does / could affect Libido (as well as focus and well being) and after reading your last reply (which spurred me to do a quick google search) i am seeing that SD is a DHT derived compound.
So I would assume you are right - that s spike in DHT is the cause for the libido spike - not just in my scenario but in general it seems