>Interesting. It does work in C# - I just ran my code thru a converter. TBH I don't think it should work in C# either - the docs for 'using' state:
>"Within the using block, the object is read-only and cannot be modified or reassigned." But this is allowed:

using (mySvc.Something = new OperationContext())
>                {
>                    mySvc.Something = new OperationContext();
>                };
>

whereas the following gives the expected error 'Readonly local variable cannot be used in any execution path':

using (var test = new OperationContext())
>                {
>                    test = new OperationContext();
>                };

Seems to me C# is letting an invalid construct slip past?

Probably, that would then explain the situation. Thanks for the additional input