I don't think the question is if you HAVE to use test with primo. The question is SHOULD you. Yes, he's 25. And yes, his body is probably use to high levels of test. And regardless of the crap thrown out about primo not effecting the HPTA, it will, over time, just like all endogenous androgens. To the degree of others - no. But his normal test will be effected, and since he's use to higher test, it could actually backfire on him. I say add 150-200mg test a week if you run primo. The only reason to not run test with primo is if you are gyno prone.
But again, I think he should run test for 8 weeks - two small pins a week. I think if he gets bunk primo gear, or underdosed, he's going to waste his money.