Right now preparing Mozart’s K 521, a real b*tch with all these fast embellishments, runs and scales in C major. To make it even worse, the piano I will play it on (Steinway B) has a heavy-feeling, sluggish action and thin sound, and there’s no way I can afford a top technician to fix it. You guys have any tips as to how to practise it and overcome technical difficulties in this case?
(ps just don’t advise “cancel the concert”, hehe) 
Do you have time to practice on that piano?
Otherwise find one with a similiar action.
I would practice ff all the way through the piece so that you are deliberately striking each finger down to the bottom of the key.
Or bet on a sympathetic audience that know’s how hard Mozart is 
Thanks, this week I can practise on that same piano. I’ll try to practise fortissimo, maybe that will help to “ingrain” it better in my “system” indeed.
just play as you’d regularly play. you’ll fuck up trying to "correct"the piano, which really isnt worth it in the end.
Hmm, maybe you’re right…
Please record it!
But isn’t that the whole ordeal with penists? Constantly adjusting to different pianos?
Yeah man.
Da worst thing is when the repeated note action is slow as hell, then there isn’t a thing you can do about it.
Usually happens on dose sheeyat practice room rebuilt pianos.
There was also a great Steinway D at school which Dey inexplicably voiced down - now it is awful. Huge bass notes and no tops at all. Ridiculously bad.
Ruined a perfectly good Steinway D. Cunt!
I was lucky in that my piano had the heaviest action of any that I ever had to play, it made other pianos a breeze even if I still had to adjust to their lightness.
The sluggish action of this Steinway could be problematic, not really sure there’s anything you can do about that other than to rehearse on the piano as much as practicable and try to work out ways to “finesse” the embellishments.
I noticed that here in Japan, a lot of grand pianos and especially the German ones have this sluggish, irregular feeling or a bad/slow repetition. It must have something to do with humidity, the climate. Also outside the Tokyo area it’s pretty difficult if not impossible to find a good technician who can adjust the action of a Steinway very well. I’ve played on brand new Steinways here in Kyushu (the southernmost island where I live) that sounded like Yamaha. It’s absolutely true what they say: a piano is never better than the technician that is taking care of it…
Btw Brew, not sure if practising on a super heavy piano on a daily basis is a good idea. There’s a high risk of injuries, and you can get a certain stiffness or harshness in your playing. I know that some teachers advise their pupils to practise on pianos with stiff actions, but I disagree with that. A good technique is not so much built on power or muscles, it’s more about coordination of movements and interdependence of the various body parts (fingers, wrists, forearms, upperarms, shoulders etc.). It helps if you have strong fingers but if your wrists or arms are not in the right position or not relaxed enough, they are useless.
of course it is, but there’s a limit to it imo. I’ve messed up too many performances trying to improve a piano, sometimes you just gotta wing it and save your dignity.
I doubt if it’ll be any good 
You may be right, though these weren’t problems I had.
I mostly remember it being a “freeing” experience to play on the lighter actions of other pianos.
Also, I knew that if I could do the Waldstein glissandi easily on my piano, I’d never have any problems doing them on another piano.