Definite fail (there are only 4 results for a flight test: pass, fail (with or without credits), discontinued or cancelled) - particularly if the diversion track was over inhospitable terrain, like Taralga to The Oaks for example.
Day VFR Syllabus C7.2 Recognise and Manage Errors - Monitor aircraft systems, flight environment and crewmembers, collects and analyses information to identify potential or actual errors
and
Implements countermeasures to preent errors or takes action in the time available to correct errors before the aircraft enters a UAS.
Definition of error - Action or inaction that result in deviation from appropriate intentions.
Surely the intention when you submitted the SARTIME was to inform the relevant people where you would be flying; and this intention is entirely appropriate. What is not appropriate is the decision not to inform them of a significant change to tracking because of some bush lawyer interpretation of AIP/Day VFR Syllabus.
Similar arguments can be made with reference to C6.2, C6.3 (Communicates plans of action - if appropriate), C6.4, C6.5 and C7.1.
Ignoring for the fact that it is good practice
Why should that be ignored?
If you understand that it is good practice, then what is the problem? All too often pilots ignore good practice in favour of a (usually wrong) interpretation of a 'rule' and the ATO is the last defence before a pilot is licensed.
Having said the above, if that was the only error you made then i'm sure the ATO would have simply debriefed you on that point and you would have passed.
do people feel that it is an actual requirement for a diversion in accordance with the Syllabus.
Yes, it is.