Also, it's prudent to consider one of those conditions to be aggressive behavior from a car behind you (horn, etc). They're proudly boasting of their non-understanding of how to fluidly pass non-lane-width traffic, so it's just safer to take the full lane and ensure they'll either change lanes or wait for a lull in oncoming traffic instead of half-passing then cutting into you.

Exactly. One of my accidents was when a taxi driver honked at me, tried to overtake and hit the front of my bike and pulled in my front tire when trying to aggressively merge back into the lane I was in. Completely destroyed the front end of my bike. I was able to jump off the bike away from the vehicle to avoid getting hurt.

There are several conditions that allow the bicyclists to ride in the middle of the lane and ignore the "stay as far to the right as practicle" rule. The most common of them is the "substandard width lane", which has been established to be any lane narrower than about 14-15 ft