Adding about the Groenesteyn:
A few years ago, I had the pleasure of sitting at the same table as Josi Leitz at Rieslingfeier. Not having any idea who I was going to be having dinner with, one of the bottles that I brought was a 1966 Groenesteyn Rüdesheimer Berg Rottland Riesling Spätlese Cabinet.
The 1966 Groenesteyn was an impressive wine in 2019. Sadly, as Josi relayed, the ancient lordly estate went downhill soon after that. Sometime in the 1990s, Groenesteyn finally shut down operations, and Leitz bought their parcels of Rottland, Josi told me that the piece of Rottland that he brought from Groenesteyn was overrun with weeds. Obviously, he revived the land, and has been making first class Rieslings from Rottland since then.
I’m not entirely sure when Groenesteyn started to decline - even I could have bottled a good Riesling from a top site in 1971 - but they had long ceased to be a respectable producer by 1992. Although Johannisberg eventually turned things around and has been making compelling wines over the past decade, Groenesteyn is the poster estate for the decline of the traditional Rheingau producers over the latter part of the 20th century.
Therefore, my expectations for the 1992 are low. It’s probably still alive, which is a testimony to the Riesling grape more than anything else. I just wouldn’t count on it being anything beyond that. Schonborn was at least hit-or-miss over their last three decades, with the occasional surprise.
As always, any additional context or feedback is appreciated.