
I think sharon you hit the nail on the head. The mental and physical maturity of the breed of pups in question is the deciding factor.
With my first litter I stuck rigidly to an 8 week minimum, but with experience have found that anytime after 7 weeks the little darlinga are ready.
Elkhound pups seem to be very physically advanced for their ages, being able to do things a lot sooner than average. Bark, eliminate unaided etc etc.
I rarely have a mass exodus, and in practice pups leave over about a 3 week period, this allows me to enjoy them to the full, but in smaller volume.
My change in approach (albeit only a few days, i.e. the first weekend after 7 weeks as my ready date) was somewhat a compromise between the current thinking that pups bond best from 6 weeks onward, and the fact that pups learn a lot from their Dam. I remember remonstrating with a Guide dogs for the blind speaker who maintained that keeping a pup beyond six weeks did it no favours as pups do not need their mother after five weeks!!! Physically maybe, but certainly not mentally.