How does critical work post-BB? + Sharp Eyes

The way I understand it, and the way I'm pretty sure it works:
Infighter critical skill is 20% more rate and +10% damage.
SE makes that into 40% more rate and +40% damage.
I have no idea how the min/max crap works, we don't have any DBs with thorns to try, but i'm told the +critrate from thorns and SE stack.

If I understand correctly, you can think of your critical damage just like a damage range. Your crits will be between 1.2 times your minimum range times the skill % and 1.5 times your maximum range times the skill %. By default, all characters have a 5% chance to do 1.2x to 1.5x crit damage. With Critical Punch/Shot, for pirates, it'd bring the critical rate to 25% chance to do 1.3x to 1.5x crit damage. SE is the only skill that I know of which increases the maximum critical damage, all other skills increase the lower end of the crit range. So continuing with pirates as an example, with max SE, the crit chance becomes 45% (25%+20%) and 1.3x to 1.8x (1.5x+.3x). I've heard that Thorns stacks with SE post BB as well, so if we throw that in, we get 65% chance (45%+20%) to deal 1.6x (1.3x+.3x) to 1.8x damage with crits.