6/10 but 7/10 if used alongside the "compete" option.
In this scenario the first move comes from the buyers of accounts, the pension funds, the bank of England (that audits the banks) and the Audit committee chairman. Realising that they need the benefits of Confidence Accounting to analyse companies they may be investing in, they ask for accounts to be prepared that way and express willingness to invest prefenentially in companies that do so. The accountants are forced by market forces to oblige. Those who are already aware and trained are able to capture some of the market.
Once the buyers (such as the Pension Funds) let it be known that THEY ARE MORE LIKELY TO INVEST IN COMPANIES THAT PROVIDE CONFIDENCE ACCOUNTS, then Companies will start to provide those, perhaps even over the objections of the incumbent accountancy firms.
This table below shows the real threat facing an accountancy company that objects. The threat of going to another accountant may be enough for the accountants the change their mind.
This scenario seems to be the one with the greatest probability of success, especially if combined with the "compete" option, which will help make the threat to "go elsewhere for confidence accounts" credible. This strategy involves using the most powerful parties, and those with the most to gain from people adopting Confidence Accounting.
Here is the next stage. Even if the accountancy companies have not agreed that Confidence Accounting is a good thing, they will still comply for fear of their customer companies going elsewhere.