We've been down this road several times. The conclusion is simple; the Yenko Deuce is a SuperCar because it has a hi-performance COPO vs. an RPO.
The '68 L78/TH400 COPO combo became an RPO the following year, the '69 COPO combo's were available as an RPO on other models (Impala for eg

, as was the '70 COPO Nova combo. So, combine the Hi-Perf. COPO with the limited production on certain models = a SuperCar. The LS6 Chevelle is usually the discussion model, and it's powerplant is certainly impressive, but it's an RPO not a COPO so it's outside the general definition.
The 1/4 mile times have nothing to do with the classification, and guys like me and Frankie should not be used as the barometer of the combination's potential.