Originally Posted by rzup
I would have thought spicing would be more stable since it would essential become extract in the high alcohol.
You're right! the spicing will be more stable compared to the dry hop. However, the perception of the spice changes as the beer conditions and ages. I've seen this in my pumpkin ale; when the beer is young, the malt character has yet to peak so the spice stands out comparatively. Then a few weeks in, when the malt flavor peaks, you get the awesome complex meld of spice and malt. A few months down the line, the spice mellows. I'm not sure why it mellows, but it does.
You might have heard this already, but a great way to spice is in smaller increments. Add a little to the secondary, wait a few days or few weeks, taste the beer and decide if you want some more. You can always add more, but you can't take it away. My theory with spicing belgians is that you're really just trying to work around the yeast character. If you're yeast is kicking out phenols that smell/taste like stone fruit or peppery notes, then work around those. I like the idea of cherries, and you'll have a hard time adding too many of those. But use a light hand on the spices. It seems like quite a few spiced homebrews I've had went way overboard.