I'm doing a Computing and ICT access course and I would say that if it's a subject you already have knowledge of, or find interesting enough that researching the topics is enjoyable then high grades are entirely practical to achieve.
On my course, most people are missing criteria for merits and distinctions by not considering the grade descriptors on the assignments carefully. For example:
Grade Descriptor: 1 Understanding of the subject
For a Merit your work or performance must:
Demonstrate a good understanding of all the points indicated, exhibit additional research and formulate relevant conclusions.
For a Distinction your work or performance must:
Show that you are fully aware of the current and latest developments in the subject, this should be supported with real life examples which have been referenced.
People are only achieving passes by meeting the criteria of the task such as on one assignment we had to explain what a CPU is. You can meet criteria and pass by pretty much rewording a wikipedia definition. Just don't do like some students and forgot to make sure your font is consistent throughout the document.
For a merit you need to back up that definition with some analysis that proves you understand your definition. And here the plagiarism checks will catch you if you aren't crafting your own insights.
And just a little extra work with a citation that demonstrates an awareness of the latest trends gets you a distinction.
But people on my course are just answering the tasks. They're not reviewing their work to consider if it checks the criteria for the higher grades even if the fundamentals of their work is good.
On a subject you find interesting, providing you have the time to commit the 20-50 hours each assignment realistically needs and you always consider the grade descriptors before you consider your work finished, there's no reason not to achieve a distinction on an assignment providing you are capable of understanding it.