How often can a fighter benefit from Avenging Spirit?

Question

Avenging Spirit is a paragon fighter feat that provides an action point whenever an ally drops:

Benefit: When an ally of your level or higher is reduced to 0 hit points or fewer, you gain an action point that you must use before the end of your next turn or the action point is lost. You must see or hear the ally when he or she is reduced to 0 hit points or fewer to gain this feat’s benefit.

How often can a player with this feat take advantage of the action point gained in this way?

Looking at this suggests no more than 1/encounter. Which suggests a secondary question: how can a fighter take best advantage of the extra action points gained in this way?

Answer 1

The feat does not overrule the limit of using one action point per encounter.

As for how to best take advantage? Paragon path features and feats that trigger off of using action points would be the obvious way.

Since the triggering condition is an ally dropping, this could be an easy way for a Cleric (multiclass Fighter) to reduce the action cost of the powerful standard action utility healing prayers like Cure Light Wounds, Cure Serious Wounds, etc.

Answer 2

You only get one action point per round. As to your secondary question: I would assume (just based on the name of the feat) that the most common use of the extra action point is to use it to charge the enemy who just dropped your ally. You have an "avenging spirit" that compels you to go after anyone who hurts your friends. Also, a nice cue for roleplaying purposes.