Online statistics gathering with CTAS and IAS - Oracle 12c New feature

I found this little gem in the Oracle 12c documentation the other day ...

A little while after, found some more info on this new "Online Statistics Gathering" ...

• Online Statistics Gathering for Bulk Loads - Oracle® Database SQL Tuning Guide 12c Release 1 (12.1) 
• Optimizer with Oracle 12c - Online statistics gathering (p.19)

And here is my demo ...
Create Table As Select (CTAS)
** Notice the "OPTIMIZER STATISTICS GATHERING"

Insert As Select (IAS)
** Notice the "OPTIMIZER STATISTICS GATHERING" again ... 

And if you don't want this behavior to happen you can use the new "NO_GATHER_OPTIMIZER_STATISTICS" hint: