O"Rourke fig look like Southern Brown Turkey,fruit leaves ,all match ,closed eye too,so it is like comparing a mother and a child,they have similar feature,that is why ,it is clearly,Dr O 'Rourke work to improve it.
Improved Celeste ,has features like Celeste,so it is an improvement on Celeste,this can be seen if one grow them side by side.
My take:Dr O'Rourke worked to improve all existent cultivars that proved to resist ,Southern climate conditions,with the idea to make them produce larger fruits,and he did get some good results.
Not perfect every time but some are very good indeed.
For ex: Improved Celeste is a superior fig compared to Regular Celeste,but for very demanding climates ,with a lot of rain like Louisiana,is not perfect as it have an eye that is a little more open than Regular Celeste,as it was taking some genes from the male caprifig,yet is much better ,than Celeste,here in my climate,because it does not drop any fruits.