This AP seems to ask the players to use the betrayal teamwork feats. My group and I have been discussing the use of them in this AP. What feats would actually be worth taking? We will have a mix of martial and caster classes.
Ally shield is somewhat useful if you have both a low AC melee and a high AC one, but not much else otherwise.
Callous casting seems to pretty much be only worth it if your ally has both Evasion and enough Reflex to dodge your Fireball/whatever; but considering that the effect is shaken, which paladins (which will probably keep being likely enemies) are immune to, and others with bonuses to saves vs fear effects will be common in the AP, it wouldn't be worth it imo.
Friendly Fire: +2 Attack roll, risks hitting your ally for full damage, and forces a standard action use (Thus not working with full attacks and many other attack actions/feats that require standard action attacks). Not good at all
Reckless Moves: Rather situational and not many cases in which it would apply. For the stealth bonus, Stealth Synergy will work better in far many more cases.
Splash Volley: Rather situational, and splash weapons aren't that likely to miss, as they are touch attacks.
Wild Flanking: Doubles your Power Attack Bonus, basically. Worth using if you have someone that is going to stack up a big amount of AC, but otherwise you might risking hitting your own ally too hard; and won't scale well when attack rolls increase faster than AC can catch up to reasonably.