I have been doing the same sort of alternating between a cigar and a fruit taste.
I know that it is a fact that people's noses get used to a particular aroma, and then it doesn't register any more. There are freshener out now that will alternate between two different fragrances. This way, the people in the room for a long time can detect a fragrance.
That is a good new project for the atomizer designers to work on. A dual-chambered and dual-flavored e-cig.
Joe Dunfee