steroidtips.com/proviron is the site i heard the nolva stacked with proviron statement from it states:
You should be aware that Proviron is also an estrogen antagonist which prevents the aromatization of steroids. Unlike the antiestrogen Nolvadex which only blocks the estrogen receptors (see Nolvadex) Proviron already prevents the aromatizing of steroids. Therefore gynecomastia and increased water retention are successfully blocked. Since Proviron strongly suppresses the forming of estrogens no rebound effect occurs after discontinuation of use of the compound as is the case with, for example, Nolvadex where an aromatization of the steroids is not prevented. One can say that Nolvadex cures the problem of aromatization at its root while Nolvadex simply cures the symptoms. For this reason male athletes should prefer Proviron to Nolvadex. With Proviron the athlete obtains more muscle hardness since the androgen level is increased and the estrogen concentration remains low. This, in particular, is noted positively during the preparation for a competition when used in combination with a diet. Female athletes who naturally have a higher estrogen level often supplement their steroid intake with Proviron resulting in an increased muscle hardness. In the past it was common for bodybuilders to take a daily dose of one 25 mg tablet over several weeks, sometimes even months, in order to appear hard all year round. This was especially important for athletes appearances at guest performances, seminars and photo sessions. Today Clenbuterol is usually taken over the entire year since possible virilization symptoms cannot occur which is not yet the case with Proviron. Since Proviron is very effective male athletes usually need only 50 mg/day which means that the athlete usually takes one 25 mg tablet in the morning and another 25 mg tablet in the evening. In some cases one 25 mg tablet per day is sufficient. When combining Proviron with Nolvadex (50 mg Proviron/day and 20 mg Nolvadex/day) this will lead to an almost complete suppression of estrogen.