How not to flinch??

[September]

I've seen the bite club thread, seen the thread asking how bad a BP bite is. My question is this, though: How do you not flinch? Isn't it natural instinct to flinch when there's something with teeth latching into you? Are some people just naturally better at not flinching than others?? Is there some way to train yourself not to flinch without getting bit?

Thanks