Being a DHT derivative does not necessarily mean something would have DHT-like effects on the prostate and hairline.
Being derived from from DHT and converting to DHT are very different.
Var is a derivative of test. By your logic it would be harsh on the hairline like test. However, it is not.
I am predisposed to MPB and lost hair on EQ and Dbol, but did not lose any on Winny or Primo.
I really think that hairloss can be a self-fulfilling prophecy. If you think you are going to lose hair, then you likely stress about it, which has been shown to exacerbate hair loss. So...Someone begins a Winny or Primo cycle... they have read numerous times about how it's a DHT derivative and how it's hard on the hair, so they expect to lose hair, putting added stress on themselves, and they effectively do lose hair... or atleast they pay more attention to it than they normally would, creating the illusion that they are losing a lot of hair.
I really do not think Primo is harsh on the hairline at all.