Exactly.

Ocminer's tool requires you to blindly trust him.
Although sourcecode is available, it is not possible to rebuild the exact same builds that you will receive from ocminer yourself.
He adds some sort of encrypted keys / connection mechanism to the file that you are not allowed to know.

Therefor you have to blindly trust him that the builds you receive actually are what they are.

But if this is his requirement, then why not just give him full remote access to your mining hardware?
From a trust perspective it's a similar scenario (just a little bit exaggerated).

This is the reason why Spreadcoin has never officialy endorsed ocminer's pool.
Because blind trust has no place in crypto.

But ofcourse you are free to enter into an agreement with him.
None of my business.