Blue#1: 15.2V gave 1.5A, 14.7V gave 1.2A
Blue #2: 15.6v gave 1.5A, 15.1V gave 1.2A

A .48 ohm resistor in series with Blue #1 would have balanced the two emitters in parallel at 15.1 V.
Weezard, how did you arrive at this? As I said before, I'm not sure which terms to plug into the equation.