Original Message

Just a PSA, there is no such thing as 4 cue. The 'cues' are cues from the flight director, you seem to be confusing / interchanging cues with axis. I assume we can blame that on 40 years of poor training. 

In 2 cue, 3 axis are being controlled but most typically you are only being provided with a pitch 'cue' and a roll 'cue' 1+1=2. There is no cue for the third axis, yaw. Keen observers will note that any of the 2 cues could be in use, pitch and power, roll and power, pitch and roll. But as mentioned above, pitch and roll are the vast majority of 2 cue operations.

In 3 cue, 4 axis are being controlled and you are being provided with all the cues from 2 cue in addition to amother cue. 2+1=3. There can be exceptions, but this is almost always power. There is still no representation of yaw.