Someone earlier on some other thread mentioned that "memos" are not really laws. I wonder if items in a memo come more under "discretion" or come under "law"?
I read somewhere - probably in one of those memos describing the outcome of a court case - that whilst a USCIS memo dictates the process or procedure that USCIS IOs must follow internally, they do not have any standing when a case comes before an immigration judge, who, by definition, is not employed under the USCIS hierarchy.
Since a judge is free to adjudicate cases based upon prior legal precedent and their own reading of immigration law as defined in 8.CFR, you may find your case being approved if you can afford the time, effort and costs associated with filing an appeal.