Can not believe this thread is this serious. ATC will not 'write you up' for this, or any initial readback error. ATC would have time for little else if every incorrect readback was entered in to the reporting system. There are much bigger issues out there at the moment anyway.
Now is the opportunity to make a name for yourself for posterity. Write to CASA and tell them what you have said here and tell them where they are wrong. You never know - maybe they will take your sage advice and you will have done something good for the aviation industry.
