T-tapping on smoke detectors connection?

Question

using a conventional fire alarm why is t-tapping not permitted?
if i make t-tapping and put end on line resistor on each side would it be permitted?

Answer 1

To make a 'T` tap work, the EOL resistors
value would be doubled.
It might complicate maintenance.
Even if it worked with the panel,
I doubt an inspector would approve.