Let me do a simple question (to gratify my curiosity). I got the basic
idea that you need to measure one quantity for each parameter you want
to control. Let's say, for a turboshaft fuel contro unit you keep under
control the power turbine speed and act on the unique parameter you can
influence, fuel injected. Other quantity controlled are just to prevent
limits excedances (TOT, Toprque, N1, ....).

Now, in the case of the "adaptive-timing ignition system", what will it
keep under control?

On a turbine engine, turbine inlet temp is the most important parameter
followed by power turbine rpm.