Combat as War vs Combat as Sport has two sides of the coin. The first is playstyle, and the second is system. Playstyle can be adapted to any game to make it play like war and less like sport. System, however, is going to limit the ability for a true war like experience because it can bind the game into a sport like experience.
The designers have indicated that having encounter powers and healing topped off is expected. As GM, you can chain encounters and prevent the PCs from resting, but forcing a fight or flight decision matrix alone, does not a combat as war game make. If you want to move away from the design expectations you need a good grasp of the rule system and how to make it work that way. Of course, you can always give the players rope and let them hang themselves if they choose to. Though, not having a good grasp on how the system works is also problematic for players.
PF2 uses a level band to determine encounters. Easy/Moderate/Severe/Extreme/Impossible. Depending on where the PCs land on the chart is going to impact their ability to fight like a war. The higher up the band, the less effective maneuvers, spells, and attacks will be. There is nothing outside leveling that can change that. Any particular combatant is going to be effected by the degrees of success in a particular band.
Crit fail/Fail, Fail/Save, Save/Crit save. Players can get items, use spells, and tactics that can give them much better chance within the degree of success band, but nothing that will allow them to change position within the band itself. Again, only leveling will move a character in the degrees of success band. Bounded Accuracy, for example, allows players at any level to apply environment, items, spells, maneuvers, tactics, etc.. and be potentially successful. Fights are difficult, nearly impossible, but still possible that are
not remotely possible in PF2
.
There is a poster I think that goes by
MagicSword that wrote a great guide about how to run combat as sport systems in a combat as war playstyle. I'll try and find it. That is certainly up my alley. I believe it was
Justice and Rule that asked me what I wanted to achieve.
The type of PF2 game that
!DWolf is certainly one I want to achieve. Though, I still understand that PF2 is designed with combat as sport as a tenet from a system perspective.