I am new at AAS, but i do believe that the original question may have been misunderstood. I do have a good chemistry background.
I have yet to figure out if 100mg of test prop is actually equal to 100mg test. Here's why, testosterone has a specific molecular weight. When you add an ester, the molecular weight of the compound increases. So to get 100mg/mL, the lab must figure the weight of the propinate ester added to the testosterone and calculate from there how much test pro will actually yield 100mg of test. Likewise, cypionate and enanthate esters have a different molecular weights as well. Therefore if the lab merely adds 100mg of a certain test with a certain ester to the delivery oil, then the tests will vary in potency per mg. But if the lab does subtract the molecular weight of the ester to yeild a true 100mg, then the esters play no role in the potency. I do not know if the labs do this or not.