This is an extremely interesting thread and I don’t think one can add much to the maillart/autolysis/dosage explanation but one key element I thing that is really necessary for the aging of champagne is good acidity. Acidity alongside carbon dioxides are preseratives and without them champagne is not going to age well. I am not going to start nit picking over vintages but I think it is pretty safe to say the vintages that go the distance have high acidity
I am deeply involved in the grower champagne scene and less so with the maisons. I think over the last decade the expressing of terroir has become an obsession for many grower producers, with this I mean, one grape sort, one site, one vintage and no or minimal dosage. And with this obsession with terroir a lot of producers have lost sight of the ageability of their champagnes.
Earlier this year at a visit to Pierre Legras, A bottle was disgorged and we were asked to taste, exquisite aromas of an aged Blanc de blancs, we were asked to guess the vintage, nobody came close. The champagne was from 1991, the famiy had given some bottles a dosage of 12 g/l and stored these for family use. The bottle then would have cost 15 francs. Legras wanted to make the point that dosage was the key element in aging and quiped that many of te champagnes being made today from his illustrious colleagues would or could not age reach such an age.
William Kelley touches upon the vinous element in champagne on his musings on Cedric Bouchard and how Bouchard’S champagnes will age like wine rather than champagne. I think we are going to see this wth a lot of grower producers. For me a really good example is Vouette et Sorbée, the Fidele vines come from Volnay, put simply aged Fidele tastes like aged Volnay with bubbles, I do not even think Vouette want their champagnes to develop the patisserie notes.
Coming back to Legras conjecture, I am not sure if he is correct. If the producer are going for low yields and low dosage, the champagne will not develop the classic aromas as described above, but will develop as a wine. The older these champagnes get the more they become territiory for specialists. The biggest problem I imagine will be the reduction in use of sulphur and I imagine the more these champagnes are transported the more drastic the effect on the ageability.
Francoise Bedel is a producer , who I personally believe does not get anywhere the amount of recognition she deserves outside of the producer community. For those wanting an introduction to older champagnes I recommend trying for instance the young versions Entre Ciel et Terre or Dis vin Secret and then taste the aged versions of these, the Autrefois or the L’ame de Terre. The similiarity of the aromatics in young and old is astounding and one has the chance to ask oneself, which do I prefer, the younger version with their pronounced freshness or the older versions which lack the freshness but have deeper, complex, mature aromas or naturally one can like them both.
Another factor which one cannot underestimate is the critical time after degorment until the Maillart is completed. Here we are talking roughly 18 months. a producer like Bedel holds her champagnes back and releases them once the Maillart is completed. This offers great stability. Examples in the opposite extreme are Laval, Leclapart and Savart, they all say they have no room to store and the champagnes are sold almost immediately after degorgement. This results in my opinion in massive bottle variation depending on how the bottles are stored in this critical post degrogement period.
I have had sublime bottles especially from Laval but also complete flops.
There are what I would call traditional grower producers Ledru foremostly but also H.Goutorbe, Camille Saves, Aubry and Pierre Moncuit where modern trends have no influence. In the grower scene I find these champagnes to have fantastic aging potential- Last year aroundabout this time H.Goutorbe released their 2008 vintage, at the time a champagne for under 50 €, on our initial tasting we were taking aback at teh substance/structure and acidity. These are dosaged champagnes that will have develop the classic aromas.
Saying all this I think the bulk of champagne being made today in the grower secne is meant to be drunk young, The 19s made in an oxidative style are so good, it is really difficult to keep ones hands of them.