The 3 heads aren't so bad. It is those dives that can easily kill you with no ability to respond.

My latest run through I got 1/2 an idea of what is going on. The dives seem to give variable warning depending on which way you're looking, and possibly position dependent too. Sometimes I get 0 warning, I see it just as I'm hit. Other times I get tons of warning, like almost 5 seconds, easily enough to evade. When I was running around, spinning around a lot I would see the warning area light up and disappear then light up again, so clearly there is some hidden mechanic to what makes the warning visible, but I'm not sure what it is. I know being on an edge looking in gives you insufficient time to react (about 1/2 second, you can't escape even with sprint on).