Excellent method, Lucinda. I did something similar, using the model provided in the Standard, but simply replaced the boxes that represent the clauses with boxes representing the company's Key Business Processes. There are more than 5, but if you arrange it right, it is clear and shows the interaction of the processes.
These can then of course be hyperlinked to the process maps that support them (if the company is set up to do this, as most are).
This approach doesn't show the link to the clauses, but I found that this particular company didn't need or care about this, except at the beginning (to give them assurance that all of the clauses were covered). To show the relationship, we created an overlay that shows where the clauses interact with the processes. After they had that comfort level, they were happy to have the model show their own company's processes and nothing else.
Fun stuff, eh?
Julie