Good theories, everyone.
For some reason, I taste the increased smokiness more on meats with less fat. For instance, when I have brisket or pork butt leftovers, I don't notice the increased smokey taste as much. But if I smoke roast beef or pork loin (not brined), the smokey taste is much stronger on the leftovers than after the first cook.
The roast beef and pork loin were also dryer, leaner meats that I didn't cook to a high internal temp like brisket and pork butt typically are, so I don't know if that has anything to do with it.
Anyone else notice that certain leftover cuts of meat are more likely than others to have an increased smokey taste?