At NHC last year, there was a club (COHO? Starnge Brew?) that had brewed the same beer 3 ways to see what decoction would bring to the game. Here are the results that were emailed to me...
"We had the:
A) non-decocted beer (dopplebock),
B) the triple-decocted beer (same recipe)
C) and a non-decocted beer (replaced ~4-5% of the base malt with melanoidin malt).
We asked which beer they thought was decocted. Results were:
In terms of which beer people liked (rank ordered), here were the votes:
After applying a basic weighting, you come up with B, C, A.
So, the main point we took away was that it really was pretty close between decoction and melanoidin. The preference likely just came down to intangibles.
Anyhow, my basic observation was that for saving 4-5 hours, melanoidin malt is well worth it."