Creampuff
I’m not sure that your example is a valid example. Of course, neither the Board nor the Director could simply say “on behalf of CASA I grant you a passport”. This is because CASA itself does not have any statutory power to grant passports – or to claim an Island or casino (as in your example). Section 53(3) clearly only works in the context of CASA’s statutory powers. On this basis, if the Act or regulations give "CASA" a power to do something, then section 53(2) expressly states that if that thing is done by the Board in the name of, or on behalf of CASA, then it is taken to have been done by CASA (similarly with the Director under 73(2)).
The issue that you are referring to seems to be covered by 53(2) – which gives the Board power to do all things necessary for the purpose of carrying out the Board’s functions. This does not seem to be relevant to the exercise of CASA’s statutory powers.
This seems to be the basis on which the DAS, for example, makes Civil Aviation Orders, eg:
“I, JOHN FRANCIS McCORMICK, Director of Aviation Safety, on behalf of CASA, make this instrument under subregulation 308 (1) of the Civil Aviation Regulations 1988.
[Signed John F. McCormick]
John F. McCormick
Director of Aviation Safety
22 March 2011”
The power to make Orders is given to CASA not the DAS. But acting under 73(2) the DAS can on behalf of CASA make an Order. If it was minded to, I think that the Board could also make Orders and do anything else that CASA was empowered to do. etc. But it obviously chooses not to do so for whatever reasons – probably fear of having to accept responsibility for any such decisions.