Brazier questions

Is there a reason people put a space between braziers? Is there a problem with having them touch?
What constitutes a brazier being in range of another? If it's firing range, then doesn't that make it impossible for two braziers to cover the same spot without reducing each others damage?
Is there a maximum number of braziers or torchposts you can have firing at one target at the same time? I was testing out a row of 6 torchposts once to see their damage, but only three lit up in reaction to the crime when all 6 were completely in range. Is this just a graphical bug?
What constitutes a brazier being in range of another? If it's firing range, then doesn't that make it impossible for two braziers to cover the same spot without reducing each others damage?
Is there a maximum number of braziers or torchposts you can have firing at one target at the same time? I was testing out a row of 6 torchposts once to see their damage, but only three lit up in reaction to the crime when all 6 were completely in range. Is this just a graphical bug?