I am going to add an other perspective. BPs run on 'auto' mode (instinct driven) and conscious mode. Auto mode is during feeding and mating and such once coiled even my most timid flighty girl can be picked up and moved to a new spot (out of her water dish) nobody home.
The conscious mode is what we speak of what you are talking about. When a snake fist arrives and is head shy timid tends to take defensive or offensive postures (balling partial balling or strike positions and maybe even a lunge) they see us as a predator or something to be afraid of. Somewhere along the line many become less afraid and there is a time of I'm going to keep a close eye on you and explore. They often will return to I think you are going to eat me position with many movements. The last stage is you are a tree and your movements and such are ignored as you are not a threat. Not all progress to all three but some do.
You might now be a warm pregnant tree (congrats BTW) and no longer pose any threat at all and the things around you are things to be explored.
Being a tree is a high compliment in snakey land. Dogs being pack animals becoming a pack is a natural event they need a pack to feel secure. A snake is instinctually afraid of large animals (us) and so it is a greater leap to be at ease with and around us of ten snakes I have 4 totally at ease with me and 3 careful but not overly so and 3 that if you move too much or are not quite still they will go defensive on you 2 of them are big time hissers too.
Another perspective.
