20. Tax practitioners must not sign a tax return under Circular 230 if the return takes a position that does not have a “more-likely-than-not” chance of being sustained by the IRS.

a. What is a more-likely-than-not chance, as defined by the IRS?

b. Is it possible for a tax practitioner to sign a tax return that takes a position that does not meet the more-likely-than-not standard? If so, what must be done to allow the tax practitioner to sign the tax return?