You're probably right, I run with the PH180 bricks through the TIU and on to the tracks. I get even more protection as each TIU channel has a TVS on the output.
We've also run our modular club that way since it was formed about ten years ago. We don't have electronics dropping like flies, even though that environment has generous amounts of shorts, bad connections, derailments, etc. If you think you have track or derailment issues on a fixed layout, try clamping 20+ modular sections together with a couple of C-clamps each and running on that! 
Yes, we also have lots of tools and other debris on the tracks from setup and repair before the show, that takes it toll.
