That reminds me of our physics teacher, who loved to go on about how German regulations were so much more advanced (this was early 80s, so not a Brexit thing) once expanding this into plumbing (not part of the physics syllabus!). He definitely had a rant about header tanks but I can't remember precisely what. I think they might be banned in Germany?
My chap cannot understand why our taps in the UK are so weird (and why we don't have washing machines in the bathroom but in the kitchen, which is another topic).
They always have mixer taps and think two separate taps is bonkers.
I have seen occasional separate taps in Germany and they usually have a "hot" and "cold" text on them, so they are quaint English design ones.
Somewhere, probably now lost to the bit bucket, there's a video of a Finnish stand-up routine about
BRITISH plumbing, and how we'll fit a high-current water heater inside a shower rather than using a Y-shaped pipe. Which neatly segues into bafflement at our toilet cubicle doors opening inwards, ostensibly so it's easier to hold the door closed when the lock is broken.
In Finland, they fix the lock.
To be fair, civilised
BRITONS do install mixer taps, but this is often thwarted by landlords and other penny-pinchers who don't have to actually use the tap.