Fusels do smooth out. They combine with acids to form esters through non-enzymatic reactions while aging. However, this process can take a long time with some batches.
Anything that causes faster yeast growth and faster fermentations rates seems to increase fusel alcohol production. However, the key drivers seem to be yeast strain (some can nearly produce an order of magnitude more than others) and temperature. And remember, the term fusels encompasses a lot of different compounds and each one is affected differently by the fermentation conditions - some may get produced more and some less. What's more, their impact on aroma and flavor is quite variable with some compounds being beneficial at lower levels, and odor-causing at higher levels. So all fusels are not bad, and some are quite important for aroma and flavor. We tend to lump them all together in discussion however, with the idea that they are all bad.
AC, there is nothing contradicting Curt Stock's results. You can make a mead that is drinkable in 8 weeks, especially if you use lots of berries, 71B yeast, and keep it sweet. DV10 is another yeast that is very low in bitterness for early drinking that can work. In a sweet berry batch, higher fusels are not necessarily a problem, just like in red wines, higher fusel alcohol levels are expected (when compared to whites).
However, if you are making traditional meads, high amounts of some fusels can really wreck your results leaving it burning hot and smelling like paint thinner. After that it may never age into what it could have been had it been managed better during fermentation.
OneCerebral, I'd love to see someone send some mead samples to the lab for fusel measurements as it would give us some really useful information to digest.
Medsen