I brewed a NB Dry Irish Stout with a twist a couple months back, I took about 4 ounces of seedless raspberry preserves, heated it on the stove to melt it and added it to the secondary.
When I bottled the raspberry smell and taste was IN YOUR FACE!
When I tried a bottle after a week in the bottle, it was IN YOUR FACE (think cough syrup).
I lamented my failed experiment and began contemplating what to do with this nasty crap.
2 weeks later I tried one again just to see and holy crap, it wasn't IN YOUR FACE anymore it was just a subtle undertone of raspberry and a light aftertaste that said "yeah there's a hint of raspberry in here, enjoy" and all rejoiced.
I think I have about 5 bottles of this left, I definitely enjoyed it!