Bessie I haven't judged for about 40 years, so I imagine things have changed since then. Back then, spur leaves were considered a serious fault and so were perfectly-paired leaves with insect/disease damage. I believe judging has become more forgiving with both of these "faults".
Of course, a spur leaf is not a disadvantage (or fault) for a cut dahlia. In fact, the set of genetically linked traits that Ted mentions is desirable and I have seen it in many great commercial cut varieties (e.g. Gingersnap, Candy Cane, etc.) The genetic "spur" gene is not always linked to the "shallow WL", "solid stems", or "tall plant" genes, but most often is. Hollyhill Tiger Rose is an example of an exception and she is a very nice, full WL, with spur leaves. If breeding for commercial cut dahlias I would not hesitate to use a genetic donor with a spur leaf (or several). I wouldn't want that trait if I were breeding for show dahlias because of the "shallow" trait that seems to be genetically linked (in most cases).
