A modern instrument like the grandpiano can do things, no keyboard in Bachs time was able to. To use those new possibilities reasonable in the sense of the musical structure of Bachs compositions and the tradition of their interpretation is the challenge the new instruments offers. The more creative leeway the instrument like a precius grandpiano gives to the interpret the more demanding is this challenge.
Here are all four parts of the Clavier-Übung for the first recorded on the same modern instrument. It is a by Synthogy detailed sampled Steinway D (CD121) build 1951 on which great interprets of the Goldbergvariationen like Rudolf Serkin and Glenn Gould already played.
(A parallel recording of the Clavier-Übung on a Pigalle harpsichord 1771 and a Silbermannorgan 1721 is here)