Axe Skill Questions

Couple questions regarding Axe skills:

Disrupting Chop: When using this skill does your attack land and do its regular damage, then interupt? I cant remember off hand. Also what qualifies as a "skill"? Any skill on opposing persons skill bar or must the skill be flagged as a "skill" to be disabled for 20 secs?

Penetrating Blow: The 50% AP, does this stack with strength/other AP mods or is this considered your new base AP for this attack only?

Thanks

Damage is done and skill being used is interrupoted, assuming you hit. Anything that is on your skill bar is a skill.

50% is your new base AP, so it''l override strent, warriors cunning etc. It will stack with skills like Judge's insight.