Your observations are correct. The DPS' course of fire does not mandate what the start position is, so it is up to the instructor to determine.
I don't recall if it was asked during my initial instructor certification or if it was the 2013 renewal class in Georgetown, but the Trooper said that the instructor determines what the start position is, but to be consistent with all the firers on the firing line.
Personally, I have students start from what has become known as the High Compressed Ready, as this mirrors Position 3 of the drawstroke. I have the student do a fair amount of dry fire practice from Position 3 before going live, & just before transitioning to the qualification have them practice the 2-second engagement on a shot timer so they understand how to time the speed of their engagement. This provides the student with multiple live repetitions from Position 3 to 4 during the qualification; if they choose to stick around after the LTC portion is complete or return for follow-on training I'll introduce Position 1 & 2 of the drawstroke to build upon the foundation they've already developed.
That's how I do it, but those that start the students already on target with the finger on the trigger waiting for the start beep of the shot timer aren't technically wrong since the DPS didn't specify a start position as part of the Task/Conditions/Standards. Personally, I'm glad they didn't, because I wouldn't want to water down my methodology if they mandated an 'on target, finger on the trigger ' standard.
