constitutional law - separation of powers

What is the relationship between the delegation doctrine and the legislative veto?

Why is the determination of whether an Executive Branch officer/official makes policy(s) so critical in the assessment of the duties of that person for the purpose of differentiating between principal and inferior officers/officials?

How do the bicameralism and presentment requirements prevent congressional tyranny and preserve the legitimacy of the Legislative and Executive Branches?

What is the distinction in constitutional significance between congress itself removing a principal officer/official in the Executive Branch and congress merely prescribing the conditions for removal of such person, and why does a formalist reject this distinction.?