It's way more complicated than what was in that pdf and than what I'm going to type up.
Very simple explanation is that pharmacies are not allowed to over or under dose generic meds by -20% or +25%.
If the label says it contains 100mg/mL of hormone, it has to contain 100mg/mL of hormone.
The difference is that generic meds are allowed to have a bioequivalence (how much of the drug is available in the average human bloodstream compared to brand name) variance of -20% to +25%.
Example:
Let's say Pfizer developed and owns the patent for brand name test e at 300 mg/mL.
This sets the reference standard for bioavailability in human blood.
Now let's say Sun Pharma makes generic test e at 300 mg/mL.
The test e still has to contain 300mg/mL, but the bioequivalence in human blood can be -20% to +25%.
Edit: Not dogging TGI...I'm actually impressed he was able to brew e at 360mg/mL without having to use EO, and the cyp came back pretty damn close.