Chris,
Having necked down .308 to 6.5Creedmoor, I'd have to disagree. In fact, the necks end up exceedingly long and require a considerable amount of trimming. So much in fact, that I have a jig that I made on a cheap Harbor Freight chop saw, to trim the majority of the overly long neck, when necking .308 down to 6.5C.
I'm not real familiar with the 7mm-08, so with that case I can't say for sure what happens when necking down from .308. What I can say, from experience, is that the 6.5C/.260/6.5x47 cartridges should not have that problem...