optionsCaption causes bound "value" to be deleted

[heberda]

I've created an observable called "ChosenName" and this is present in my input data.

I then bind this to a drop down which uses the optionsCaption markup.

Now when using "toJSON" is appears to have gone! I have found two work arounds but I might fork and look into a fix, you never know :)

http://jsfiddle.net/heberda/k0ofx859/4/