He takes the view that SEAT/VW-Audi spent billions of €s/£s developing the 1.8T's performance vs reliability parameters, so it's dumb to go & alter the setup.
True but VW have made themselves a double edged sword, they promote cross brand use of components which is why the 1.8T is used in Skoda Estates, Audi TT's and 50 other makes and models.
It's good news as they can keep costs down.
The downside is that a recall could cost millions accross lots of brands
So I'd argue that they play things VERY safe to be sure they don't get stung
My experience
40k Miles in a remapped Golf GTi 1.8T and 50k Miles in a remapped LCR no big issues.
The basic engine is so strong that a 180bhp engine can have a turbo swap, be running 330bhp+ on standard internals.......there are plenty of examples of this type of conversion.
How far you can go with a 1.8T......well one forum member is aiming for 600bhp+