Yitay: It is certainly denying the validity of the Torah Sheba’al Peh according to the Geonim’s approach, which seems to have been adopted by the Chazon Ish and our current society. I could definitely hear a claim that that isn’t Apikorsus within the Rambam’s approach, though, I guess. Unless that counts as denying “Dikduk Echad MiDivrei Sofrim.”
