I never known it to "not work", as it is extremely potent.
However, results are not necessarily indicative of a steroid's legitimacy or its potency. The circumstances need to be evaluated before drawing conclusions. Allow me to explain.
For example, if we are looking at a very advanced bodybuilder who has been using 4 grams of gear for 5 months...and he adds in 300 mg of trestolone/week for 30 days, what can we really expect? Trestolone is great, but it's not going to produce much of an effect (in terms of actual growth) under those circumstances.
However, when compared "head-to-head" against other non-methylated AAS, on a mg per mg basis, trestolone beats out EVERYTHING in my opinion.
So, I don't think there is ever a time when it doesn't "work", but there are times when it is just a small part of a much bigger cycle. Under these circumstances evaluation becomes difficult, if not impossible. There are also a dozen other factors that could influence someone's rate of progress...but when it comes to trestolone itself, I think we are beyond dispute regarding its effectiveness. Anyone who denies this at this point is just misinformed. I understand why some people are still leery...because it is a "newer" drug, but there has been plenty of feedback for several years now..and a lot of people have quite extensive experience with it. At this point it has already "proven" itself. Will everyone respond the same? Of course not, but it is a potent muscle builder when compared on a "per mg" basis. There is no denying this.