I think it's because the HE is designed to be so efficient there is less margin for improvement so to speak with out major changes to internal components ie pistons/crank etc, so to turbo it and get big-ish power is way beyond what it was designed for, and seeing as it was designed and produced so efficiently it would take significant changes to both components AND production it would render it economically unviable.

I dont think anyone can accuse Ford of doing the original FRS 'On the cheap' as it cost the £27000 to produce each car and sold each and every one of them at a significant loss, hence why they would be reluctant to produce a car that was so far removed from its general production line in the future.

Essentially the same problem AVO and Boreham have faced in the past. Specialist production facilities that are labour intensive and geographically and conceptually so far removed from the 'standard' production line just dont make economic sense. It's not necessarily about making the best car, its about making money at the end of the day.