Lucky you were...
I am a bit envious,,,
Behind the decreasing virtuosity we can listen the powerful expressive tone which almost no pianist i know of , save a Sofronitsky , can produce...
The ruins of his playings reveal a deepness that is nowhere to be heard...
I'm pretty sure I saw Nyiregyhazi in performance during the guy's momentary, end-of-life resurrection of his career. It was in L.A., I can't remember exactly where the concert was (The Dorothy Chandler Pavilion?) but I had a truly excellent seat. The audience wasn't large but it was absolutely worshipful. Nyiregyhazi played with a playful, indulgent "why the heck not?" affability. Unfortunately, he only had a glimmer of his once magical chops. In any case, it was a heck of an experience.
For example this :
I pick the "evening bells " and the christmast piece to show after the madness of Olbermann valley or Mephisto how touching and exquisitely hypnotizing in his effective tenderness and grace E.Ny. could manifest pure heavenly grace... At least at the same level than Brendel... If not, i will say that E.Ny. play with a suplement of grace in my opinion... Because here E. Ny. is more delicately fluid than even Brendel and the total resulting piece is more integrated as usual with E. Ny. with pulse behind the horizontal melodic line ... With Brendel it is more like many small successive scenes...
I had only Liszt: Weihnachtsbaum with Brendel :
https://www.youtube.com/watch?v=Rn9zi8cLAoA
The same piece by E. Ny. for the 4 first minute and a few seconds.. but observe that E.Ny. is repeating the complete first section, though it's not written in the score.
https://www.youtube.com/watch?v=O0S1KDOC8is
After 8 minutes 19sec. : The "evening bells" is in the E. Ny. youtube selection . But i did not have Brendel playing to compare with...