I'm looking at doing something like the Southern Tier Creme Brulee Stout soon, but not quite so nuts as they have gone with it. The "clone" recipe in BYO is highly suspect in my opinion in a number of ways, so I'm reluctant to do what it directs with the vanilla; "3 vanilla beans split and deseeded steeped for 20 minutes at end of boil then removed".
I'm feeling more like rum-soaked beans into secondary and/or serving keg may be the way to go. Southern Tier uses extract anyhow, so it's not a 1:1 comparison.
For a 5 gallon batch, if I spilt, scrape, and dice 3 beans into 1" long chunks and add them to the serving keg will I get noticeable character? If not, what amount/duration would be better in secondary? I generally do not secondary and I don't want to add the beans to primary.