I really like to be spontaneous in choosing...

I really like to be spontaneous in choosing the pair we swing with, but my wife wants to know like... everything about them. Sometimes we need 3-4 meetings before the swing happen. How can I convince her, for at least one time, to close her eyes and pick

someone? I've already tried lines like: it's just for fun, let's see what happens, only this time etc. Need your advice guys!