Although I am usually not inclined to posit speculations on why a particular drug does or doesn't do something, in this case I will. Im guessing that the higher doses of Anadrol cause enough appetite suppression (at least anecdotally) to make eating rather difficult. It can also increase insulin resistance and glucose intolerance (5). This has the effect of making macronutrient absorption more inefficient, and could also be a factor in reducing gains when the dosage goes over 100mgs/day. Unfortunately, Anadrol also has a reasonably profound effect on your body's natural hormonal system, on par with most other oral steroids , but not as bad as most injectables, and its certainly not as harsh on your lipid profile as many anabolics are
It is interesting to note that oxymetholone does exhibit some tendency to convert to dihydrotestosterone in the body, although this does not occur via the 5-alpha reductase enzyme. Oxymetholone is already a dihydrotestosterone-based steroid, so no such alteration can take place. Aside from the added c-17 alpha alkylation (discussed below), oxymetholone differs from DHT only by the addition of a 2-hydroxymethylene group. This grouping can be removed metabolically, reducing oxymetholone to the potent androgen 17alpha-methyl dihydrotestosterone (mestanolone). 387 There is little doubt that this biotransformation contributes at least on some level to the androgenic nature of this steroid. Note that since 5-alpha reductase is not involved, the relative androgenicity of oxymetholone is not affected by the concurrent use of finasteride or dutasteride.
Although the debate rages on (and probably always will) there is a controversial solution for getting the best of both worlds, and that involves using both compounds together in a cycle. Although both of these oral compounds are liver toxic, you can use them safely at moderate doses during short cycles and alongside a liver protectant supplement. The most common Anadrol Dianabol stack involves a 4-6 week cycle during which you take 25mg of Dianabol and 50mg of Anadrol per day. The synergistic effects are quite noticeable at these doses. In short, using the two together counteracts many of the side effects due to the low doses of each, including appetite loss, aches and pains, and even fatigue.