I think the key point about scrotal application that although you get a rapid absorption/initial peak of E, you then get a quicker decline. Whereas other transdermal areas like your thighs looses out on that initial peak but has a much slower and steady absorption rate.

I started to rotate between scrotum, thighs and bums to avoid overloading the one area, I think the Oestrogel instructions talks about overloading skin areas so advice rotating between thighs, shoulders etc.

It's one of those, horse for courses, what each of us finds best suits us.