Sultan
Kitana, Scorpion
If I'm -4 that means my f4 will reach my opponent in 11 frames. If I'm spaced at the edge of f4 range, and my opponent has no options that travel that same distance or further in 11 frames or less, that means a follow up f4 is now a more viable option when properly spaced.Shinnok is still -4 after the gun, regardless of how he got there and where he ends up in proximity to the opponent. A competent opponent will start pressure accordingly no matter the distance. It's nice in theory what you're saying because hardly anyone knows the match up properly but in the long run it will not be practical.
Simply put, being -4 in an unadvantageous position and being -4 in an advantageous position are different things, and one is clearly better than the other.
If I'm playing Shinnok, I don't want to be face to face at -4, I want to be just outside of most jab or d1/d3 ranges. I don't want to give my opponent options.
A competent player or not, advantageous spacing is advantageous spacing. I don't see how that losses practicality.