WOW! Nice Wheever!
I'm assuming this problem only Trek's 4.X series Domanes.
I had to go check my bike after reading this...
For what it's worth, I'll report that I have a 2015 Domane 5.2... it's about 8 months old now, 1500+ miles.
No damage on the seat post that I can see.
However, though my seat post looks similar to the Domane 4.5's, it isn't (it's listed as a Bontrager carbon, 2-bolt head, 27.2mm, 8mm offset).