Setting listBehavior to false = 'break' ?

[Mark Powell]

I have a preOpenStack handler that sets the context-specific properties of
one particular field (sometimes editable, sometimes clickable, etc.).  When
using the following line 

  set the listBehavior of field "foo" to false

in either a switch or if/else construction, the debugger shows that my
handler acts as if there is a break statement following this line,
immediately exiting the construction without performing any downstream
instructions.  Can someone instruct me on what I am doing wrong?  Is there a
bug in the system or is there a bug between my ears?  My config is Rev.
2.0.1 on Windows.

Thanks in advance.

Mark Powell