ESO has been fairly tight with hard data. It is better, but no real idea how much better. To figure it out you would have to break a lot of things with and without it to get a data set. As the game has not even had the official street date... that level of info with solid backing is a long way coming.
Nothing is impossible... there are only differing degrees of probability.
It's really easy to find out if anyone has gotten to that level yet. I'm asking to see if anyone has done so. I know there are some people out there that have power leveled blacksmithing and could probably provide insight.
I am not saying people cannot level to there or take the perk... I am saying to reverse engineer the %increase the skill perk provides with a RNG will take a lot of work and time to do the math. Maybe someone has and will post, but I think for a solid number you need to break 1000 items or more both with and without the perk selected to get a valid data set.
Nothing is impossible... there are only differing degrees of probability.
Temper Expertise, not Metal Extraction. You are mistaking the skill. The one I'm referring to raises the chance of tempers for improving item quality. It's a set value that is available in the tooltip when using the temper, once you've leveled the skill. For example, Dwarven Oil is a 15% chance before Temper Expertise 1 and a 23% chance after.
Getting it down to 3 of 5 is what it was when it was maxed out. That was beta and things may have changed. The drop in required tempers was pretty high for the top level but along the 3/5ths line.
Nothing is impossible... there are only differing degrees of probability.