I let this thing marinate and I come back to this... After all this whole arc??!@?!?
I could feel the author smiling at the ragebait they pulled out with this... Gosh... I'm dropping this mang I can't do it.
All things considered I think the author wrote these characters out quite honestly for their situations— a hero that cannot immediately trust someone responsible for so much of his own suffering, the demon princess being so upper class and then unable to properly interact & address that...
At first I thought the skill was gonna be like "Strategizing the whole plan far enough to your favor that you get granted the victory" or something, but no... It's just autopilot ez mode the skill.
...Well there's always another manga in the horizon.