From CAAP 234-1(1)
"This publication is only advisory but it gives a CASA preferred method for complying with the Civil Aviation Regulations (CARs) 1988. It is not the only method, but experience has shown that if you follow this method you will comply with the Civil Aviation Regulations. Always read this advice in conjunction with the appropriate regulations."
The CAAP gives "a CASA preferred method", which is specfically acknowledged as "not the only method" of compliance. Your only courtroom obligation in this regard would be to establish that the method you chose complied with the Regs in a way that was as good or better than the method in the CAAP. That would not be hard at all.
The court is required to take any CASA guidelines into account. It is not required to take into account your compliance with those guidelines. There is a very big difference between those two. If the method you chose gave a result equal to, or better than, that achieved by simplistically following the guidelines, then your defence to this part of the case is sounding pretty solid.