Pope Abuse

[FactionHeir]

I've noticed a few odd items about Papal warnings.
1) If you are sieging a city/castle and the Pope warns you to stop fighting, you can keep up the seige and take the provice so long as you don't assault. Logically the warning should mean "Stop the seige", but thats not how its handled.

I get excommed for that if the papal warning is "you may be excommunicated". If its a warning that you may only lose standing, then you lose standing by keeping up the siege.

2) Blockades can be kept during a Papal warning without you getting in trouble with the Pope, but you can't start one without getting him upset.

Correct, he doesn't care about that

3) When he gives the warning, the only types of combat you can be involved with are siege related without failing the mission and getting the Pope upset. That means you can sally forth to get rid of a sieging army or fight an army that sallies forth, but you can't fight and open battle even if you are the one defending. I've had a couple cases where I had small units moving on the campaign map that got attacked. If I wasn't able to withdraw and I was stuck fighting, I'd get the Pope pissed at me.

Not quite. You can freely attack anyone inside your lands without the papal mission failing. He may give you a mission to stop attacking when you attack people in your lands though but it never fails if you follow the above. As such, you can also attack the besieging army from the outside without repercussions.

4) If you bribe your way into better standings with the Pope than what your enemy has, you can continue fighting with them (and accept the loss of the mission) without worrying much about really loosing standing. This may not always be the case but I've yet to get excommunicated for doing so.

Again, only works if the missions is not "you may be excommunicated" only if its a lesser penalty.
if you have the excomm warning, you can bribe yourself up to perfect and he'll still excomm you if you fail the mission.

[Henry the Fifth]

Check to make sure that in #1 of your post that the amount of turns left in the siege is not the same or greater than the amount turns in order to not attack the faction. The Papal command use asks you to cease hostilities for seven turns if you have at least seven turns in your siege, the Papal ban will cease before you resolve the siege, which may be why there is no penalty extracted.