As for the r400, in the last couple of week I have been going of the idea of having one ,a lot of people are saying the price will 45k base which is way above my pay grade.
Also watching the latest track battle between the RS3 & golf R has made me think how good the R is anyway& adding more power doesn't necessary make it any faster on the twisty bits.
Then there is the name which a certain member on the golf r forum likes to call himself has slightly tarnished the name, & has put me off .
I've never been tempted by the R400, as I need practicality as much as performance, as my car also doubles up as the family car, (our other vehicle is a an/truck)., plus I know my limits! And as you rightly say, in real world terms you are never likely to make the most of that extra power. Different story if you track it of course.
As for the the R400's namesake on vwroc, I rather like him, although he's become a bit boring of late. Needs to up his game.