Just an anecdote that may or may not be related:

I brought my Domane road bike to the shop yesterday to replace a broken front derailleur cable. While it was up on the stand and the tech was looking at it, he noticed things in my tire; the stock, heavy, Bontrager R1 Hardcase Lite tires. We picked about 6 little glass chips out of it. (none in the front)

Those tires may be heavy, but with them and butyl tubes, I haven't had one flat in 5,000 miles. Probably 1/3 of that is city riding, too.

This has me thinking that maybe (the better) TPU tubes are a good compromise inside of heavy, puncture-resistant tires.

I have a pair of Amazon ChiComm TPU tubes for the Domane waiting to be installed, but hearing of easy flats with name brand tubes has me worried.

Can't wait to hear John's experience after a couple hunnerd miles riding around Jersey. I'm sure he'll be carrying the TPU patch kit as well as a couple butyl tubes for awhile.