"Motorad" high-flow thermostats

I’m amazed how this goes around in circles.

Has anyone measured this and bothered reporting? Yes.
Have people acted on this by either putting a foot on their thermostats or a thicker base on the housing? Yes
Do any of you read the archives? No.
That includes the old photo albums… Oh does it?
Where do you suppose 42mm comes from?
Shall we start another thread titled "my gauge shows just past “N blah blah blah”?

kind regards
Marek