He is talking about test D and the difference is 72% vs 66%
So 2ml of test E 400 are less potent than 2ml of test D 500.
Plus test D 500 is pipless for the majority of people, test E 400 is hit and miss.
Test D 500 is a lot smoother in the delivery too and the more you increase the volume of injection the more the difference in total mg of testosterone vs volume of oil become big.
3ml of test E 400 are 864mg of testosterone
3ml of test D 500 are 990
Quite the difference
2ml of test E 400 576mg
2ml of test D 500 660mg
So even 1ml of test D 500 is stronger than 1ml of test E 400.
Your math is not mathing.
Assuming stable levels are reached on both ester.