Bread-Bakers v105.n016.1

First, you don't know the relative strengths of the two ingredients in the 
final flavor.  There's no reason to assume it's half and half.

Second, you don't know how relatively intense the flavors are in citrus and 
vanilla extract.

Third, you don't know what the carrier is for the flavors.

All three of those factors would make it difficult to get the same results.

But it might be fun experimenting, and maybe the amounts involved are so 
small that it doesn't make any difference.

Jessica Weissman