In the screenshot below, the active character had the Pathfinder and Dagger Mastery perks, and so could have moved ahead 3 tiles AND made one attack with the dagger on the same turn, but it was not possible to move straight ahead and the character was forced to move around the higher tile (occupied by an ally), thus using all the action points to get to the destination tile.
You can see in the Tundra tooltip that the Action Point cost (for moving up/down a level of terrain) was 2+0. So, he could have gone straight ahead (towards the highlighted tile) for three consecutive tiles, using just 6 APs, and then could have used a dagger attack for 3 APs. If the tile immediately in front hadn’t been occupied by an ally, he could’ve moved one tile at a time, using just 2 APs per tile moved, but the inability to move one tile at a time meant that the pre-selected route had to be used.
Yes, I have also noticed that. When moving to a opposite angle, you can have only one way(while the fact is you have 2, but BB can’t choose the direction to the opposite angle). This is not bothering when both directions have no restriction. But when you have the default route under enemy’s control, and the other route occupied by an ally you cant go to the opposite angle without passing enemy’s zone.
The game took the route with the lowest fatigue cost from what I can see. I suspect Fritz has the Athletic trait. Moving “over” his own brother would result in a cost of 12 Fatigue (3x height level change) and the path that the game shows only costs 4 fatigue.