It doesn't make any economic sense.
The ThermalBanks (their word and trade-marked) is below the foundations of the building, so this is only for new build. If your doing a new build house, and spending this amount of money on an assisted ground source heat pump (think $$$$, particularly if you live in Germany ), you may as well spend it on extra insulation and then you wouldn't need any heating as you'd have a Passivhaus building.
Complexity for the benefit of the consultants and their fees.