When (or does) The Sweetness Fades

I've been exposed to an environment in which the folks responsible for making the wine like them soft and sweet. Dry is almost a dirty word.

Two wines I've seen, one a medium body, not all too dense and tannic Syrah with a heavy splash of a sweet white and the other a blend of roughly 2/3 Petite Sirah and 1/3 Late Harvest Zinfandel, both tasted fresh, fruity and kind of sweet with better than 1% RS in each when they were finished. And that's the way, uh huh, uh huh, they like. Let's not argue taste. The question is whether this sweetness fades as a general phenomenon.

The Syrah (blend), an '07, was round and sweet at bottling in November of '09, but now it is dry and tannic and rather tasty to my taste buds. The PS/LHZ blend is an '08 and still in the barrel. The original sweetness lent by the LHZ is gone. I was asked to taste it blind and make a comment. My comment was that it tasted like PS and Zin, some fruity Zin character up front and a coarse PS finish. Faces dropped. It was not the sweet, harmonious whole the creators intended.

I'm sure a lot of stuff could be happening here from the character/development of the wine to handling issues. What do you think? Just for fun now.

perhaps a data point, I think my TN conveys the experience:

2000 Ridge Zinfandel Late Picked York Creek

11/22/2009: Unexpectedly this was neither particularly sweet nor volatile. Despite 15+ abv and the label description, it was just a bit more than off-dry, almost suitable for dinner. We enjoyed this with an intense chocolate cake, compared with the wine seemed rather light. While these grapes may have been harvested late, there was no sense of overripeness, rather surprising restraint, acid and light wood. Overall more enjoyable than expected.

Somewhere back in the Dark Ages I attended a symposium of Alsace producers in which it was recommended that their rieslings be aged at least ten years so that the sweetness might fade, allowing the wine's true terroir to come to the fore.

(At the time, I thought they were nuts. Upon reflection, I still do. Alsace riesling without that delicious fruit? Why would I do that?)

Dave, was your symposium on late harvest (vendange tardive) Resilings? If so, the advice would make sense.