Holacracy Community of Practice Archive, 2015-2019 Community Holacracy Web Site

At the risk of repeating some of what's already been clearly said above(but sometime rephrasing can help). Holacracy doesn't have all possible necessary anti-bodies to avoid members from polluting the organization with consensus logic, it does have all the required tools to make that choice explicit though, and in some specific "problem domains" consensus might still be a good option.  One thing holacracy does is to encourage the organization to attach accountabilities to roles and perform work according to those accountabilities. A Circle is a role, but it also contains roles which can take responsibility to perform process steps on behalf of the circle, more so when you are breaking down a circle accountability. Now if the process steps required to approve a budget require specific vertical skills that need to be engaged in some sort of sequence you might be looking at a possibly helpful role-ashionship  right there: something you can encode in accountabilities/policies/domains   contained in that circle so  that the final result produces something like: 

Role y  approves the budget according to the best practices published by role x and integrating the objections of roles z,k after submitting it to external consultant Y for review... (just an example with no practical value)