I did extensive testing and the burn damage from the burn sticky bomb is being reduced as the player increases skill tier.
Steps to repeat:
1) Equip the burn sticky bomb
2) Equip zero +1 skill tier core attributes on gear
3) Equip the technician specialization
4) Respec your technician specialization tree so no points are allocated
5) Go to the firing range
6) Shoot the 5m target with the burn stick bomb
7) Note the damage per tick of the burn damage
8) Return to the specialization desk and unlock the node that gives a +1 skill tier
9) Return to firing range
10) Shoot the 5m target with the burn stick bomb
11) Note the damage per tick of the burn damage
Repeat steps 2-11 six times, but on step 2 increase the amount of +1 skill tier core attribute pieces by 1. (Make sure these +1 skill tier items being equipped provide no %status effects or %skill damage)
THIS IS NOT a technician tree bug, this is repeatable using this method as well:
1) Equip the burn sticky bomb
2) Equip ZERO +1 skill tier core attributes on gear
3) Go to the firing range
4) Shoot the 5m target with the burn stick bomb
5) Note the damage per tick of the burn damage
6) Go to recalibration station
7) recalibrate an items core attribute to +1 skill tier
8) Return to firing range
9) Shoot the 5m target with the burn stick bomb
10) Note the damage per tick of the burn damage
Repeat steps 6-11 six times.