Well, I'm about to sign off a large single thermalfluid system which has been retro fitted into an existing plant.
This system breaks every unwritten rule in the book, but with a miracle of engineering, has been installed into what can only be described as a rats nest of pipes.

I am for some reason nervous of what is going to happen during commisioning. if the engineers on site don't install things properly (ie bolting the pumps down to resist the pressure thrusts, ensuring guides etc are in the correct place)

I am by no means 100% confident that these things will go smoothly, we'll see