Frontloading brings your levels up quicker, this is very beneficial when using those long esters.
Nandrolone does convert to estrogen.. but much less than testosterone.. some research shows 80% less conversion than test. What is of more concern is that Nandrolone has an affinity for the progesterone receptor. This has the same side effects as estrogen.
Some argue that Nolva works for both estrogen and progestin induced gyno because the progestins just exacerbate the problems of estrogen. As Nolva is selective in breast tissue, it is said it can help with both cases.
Others say this is not true and only saw reduction of nandro/tren gyno from Dostinex/Bromo or high doses of B-6(400mg) with Vitex Agnus Castus(400mg-800mg)
Those are the 2 schools of thought on the subject.
To be safe, when I am running Test and Nandrolone at the same time, I take Dostinex(0.5mg E5D) and Raloxifene(40-80mg ED) or Nolva(20mg ED) when I notice gyno symptoms. I feel it's better safe than sorry.
It should be noted that Dostinex and Bromo are Dopomine Agonists. There are no studies to show the long term effects of using these compounds for our purposes. Some fear that it can cause the onset of Parkinson's disease.
A good side effect of using Dostinex is that seeing as it lowers prolactin so efficiently,it can give the man the ability to have multi-orgasms in a session. It does one hell of a positive number on your libido.
It's good you're doing research. Keep it up, we're always learning.
Just my 2cc's