Can "this" be acheived on an accustic piano: (sorry I don't know the musical term for "this", but it is essentially trilling the same key as quick as possible)

-If not, why not? What action is needed in order to do so?

Just curious.

-JG

(I also want to get away from the frustration, what we call "the recording game" )

Yes, "it" is enabled by the "double escapement action". It is not reliably feasible on an upright piano.

The double escapement action was developed by Sébastien Erard in the 1800's and is now ubiquitous among grand pianos. (Chopin exploited this innovation to its maximum. A perfect example is seen in his 10/7 etude; notice the pattern of double notes in the lower voice of the treble clef). Double escapement occurs when the jack is reset beneath the hammer as the key is partially released. This allows the note to be repeated quickly without the action parts returning to their original at-rest positions.

It's a good thing.

Pete

It's an awesome thing...if I ever get my pork-chop hands on a grand piano

Thank you for the reply.

Yes, that's the effect of the double escape mechanism.

Regarding Chopin however: he preferred to play on Pleyel pianos (as opposite to Liszt e.g.). Pleyel pianos did NOT have the double escapement action that time. That means, it is at least questionable that Chopin eploited this innovation.
However, the Pleyel pianos did have a short keyway, and had a very light action in conjunction with light hammers. Maybe fast repetitions were possible too without that mechanism.
So Chopin e.g. preferred to use the same finger for key repetitions (in opposite to the useage of different fingers, e.g. 4-3-2-4-3-2 and so on), I think that was stated somewhere in the Eigeldinger book "Chopin as seen by his pupils".

Someone who really exploited the double escapement facility was Ravel. Listen to the beginning of his Toccata (Le Tombeau) for example. That is not possible without the double escapement.

At least many of Liszt's works require the mechanism!