Hi Jake,
My understanding is you have something roughly equivalent to this (I'm using menus instead of calendar fields for simplicity):
{formmenu: yes; no; name=selection}
{if: selection}
Calendar 1: {formmenu: Yes; default=No; name=calendar1}
{else}
Calendar 2: {formmenu: Yes; default=No; name=calendar2}
{endif}
{if: calendar1}Apples{endif}
{if: calendar2}Banana{endif}
I think you would like to change it to something like the following. By checking the main menu selection when also displaying the words, you can get what I think you are looking for:
{formmenu: yes; no; name=selection}
{if: selection}
Calendar 1: {formmenu: Yes; default=No; name=calendar1}
{else}
Calendar 2: {formmenu: Yes; default=No; name=calendar2}
{endif}
{if: selection and calendar1}Apples{endif}
{if: (not selection) and calendar2}Banana{endif}
Does that help?