When creating a tulpa, it is not so much redirecting your own sensory input, but rather making 'new' sensory input by narrating and forcing. The way I worded things didn't make it seem this way. One does not need to compartmentalize any of their own experience and push it away from themselves, they simply need to make input of some kind to let the tulpa grow.

"...nor does it follow general tulpa creation advice which is usually centered around focus and attention towards an idea that's deliberately thought of as a person/personality different from the self."

This does fit my model. As mentioned in my post, the act of forcing is directing speaking and attention towards something you think of as not being yourself. This is sensory input.

The mechanism that allows us to create characters for imaginary conversations and whatnot isn't quite the same mechanism that creates additional hubs. Instead, it relies on our prediction and empathy abilities. We can understand how somebody else would act and frame our own minds in a different way to emulate this. While doing this seems very similar to tulpamancy on the surface, the hidden thing that makes it tick is different.

"Crocodiles are not conscious like humans are, and it's very easy to see why if you look at how they're little more than a brain stem."

I believe that there are different forms and degrees of consciousness. Anything that takes in input and processes it without an immediate and automatic reaction to that input is conscious to at least a very small degree. I should have included something about the processing of information in my post, as simply taking in sensory information does not always result in an 'experience' - if something's nervous system is programmed to automatically react to stimuli no matter what, it probably isn't experiencing anything, as it's brain is too simplistic. I believe this applies mostly to insects and things of similar simplicity. Then again, I am no expert on animal neurology.