My position doesn’t require a lot of faith in the FBI.

If they fail in parallel construction, they always have the option to continue. For the vast majority of cases where opsec isn't 100% foolproof, we hear about them. For the few cases where it was foolproof, we just don't hear about them.

It requires faith that they prioritize keeping such abilities a secret rather than prosecuting, and again, I do not share this faith.