I can't understand why we have had all this recent discussion
about piano keys not moving and some people modifying their piano
to make them move.

In the main, English pianos were made with rear weighted keys
specifically to prevent them from moving.  This is the correct design
intent.  There are good reasons for not allowing the keys to move
and these have been discussed at length previously.  The only reason
I can see for having the keys go up and down is to amuse little
children who are more interested in this than the music.

Anyone considering modifying their piano in such a way should
reconsider their position in terms of instrument originality and
musicality.  Why 'fix' something that isn't broken?

There are, of course, exceptions to the rule such as pianos with
under-action where key movement is unavoidable, but these pianos
usually have a double valve system to give a better response.

Best wishes from Nicholas Simons, who doesn't like his keys to move.