Amazon's Critical Strike and Penetrate Nodes... How do they work exactly?

Here's the full text of each for reference:

Critical Strikes:

Chance to Hit with Attacks can exceed 100%

Gain additional Critical Hit Chance equal to 25% of excess chance to Hit with Attacks

and

Penetrate:

Attacks using your Weapons have Added Physical Damage equal to 25% of the Accuracy Rating on the Weapon

My questions are:

For Critical Strikes, hit chance is calculated on a per hit basis, right? So really the additional crit chance is dependent on your accuracy, their evasion, and the distance between the two of you. Are there buffs or debuffs that work with this? I think Hobble is the most obvious one to try and max out the bonus, but Maim and Blind both reduce evasion, right? Does Pin do anything?

For the added weapon damage from Penetrate, I'm taking this to mean that a modifier that gives 600 accuracy also adds 150 flat phys to the weapon damage, right? Is the added damage affected by the % increased phys local to the weapons, or is it added after the fact? What about Iron runes? I have to assume that it's completely separate from the weapon, as comparing absolutely perfect weapons, it pretty much perfectly breaks even in that case. But of course, accuracy is a dead stat for most builds, so it's still good from that perspective.

Also, I've been seeing some mention of "accuracy stacking" as an emerging archetype. I think there's some benefit to getting your baseline accuracy high (which you can get with dex and a small amount of investment), but I think hobble is the only practical way to actually get to 150% hit chance. The hit chance equation means you really hit a wall around 130 or 140%, and it's better to just reduce their Evasion.