Leathercraft from 73 to 110.
Using Macaron, Shaper's Shawl, Ionis, and this double campaign.
I found between 94 and 104 skilling on Aetosaur Gloves my skill up rate was around 90%.
After 104 it dropped to about 75%. And again at 108 it dropped to around 45-50%.
Leveling a craft to 110 seemed so ridiculously easy, I wondered why I avoided it before. And then quickly realized... it was all because of the double skillup event.
Pardon the absence of any higher level screenshots. It was ridiculously easy all the way up.