ICAO D
Your point is well made, so why beat around the bush - unfortunately, my research shows that when you have someone who seemingly left an organisation under a cloud and now wishes to denigrate or payback anything related to what that organisation does or supports (ADS-B in this case) - logic and even a chat over a beer will not work.
You are a low time poster but if you follow the threads here and were to review other forums you would find the one, sometimes two, posters as common causes of the angst. The post 3 Aug 22:13 will give you the clue.
Most of us prefer to follow the thread line - it is unfortunate the agro of the one or two detractors sometimes engenders a response, as occurred to Bob from at least three (unrelated) posters on the weekend. I have already apologised that I finally took the bait and was one of that three.
Back on track - as regards the CAAP, an expert legal opinion would certainly be well received.
In that regard, do not allow Bob's confusion and drift to mislead. That's why I said right answer to wrong question.
The CAAP is a CASA publication, well vetted before issue. I do not find anything in it that suggests one should breach any higher order rule or regulation. The CAAP gives instructions on GPS use under the VFR - the emphasis being that GPS use is an operational consideration but the onus rests with the PIC to ensure compliance with the flight rules - in this case VFR. No different to the PIC having to also aviate and communicate, and ensure fuel sufficient, etc, this CAAP merely advises on one small operational consideration of the flight but a most significant one as regards avoiding a possible head to head (more so below 5000').
My argument would be that anyone following the AIP or CAAP - after all, operational documents issued by the regulator - would not be in the hypothetical concern you raise of "The existence of the recommendation (eg a CAAP) may mitigate the sentence and/or penalty" - rather, the average person would anticipate that the beak would accept compliance with operational material issued by the safety regulator as exemption from sentence or penalty under a reasonable man hypothesis. In logic (perhaps questionable re legal decisions) the regulator should not issue any instruction in contravention of its own regulation (not that I think it has with this CAAP).
My reason for raising the GPS offset, and CAAP, is that an ADS-B mandate and subsidy opens the way to far more GPS navigation and risk of head on. It may even be wise to issue a reminder re the CAAP should the 'Son of JCP' be born.