Thanks for your input, but I was specifically responding to the claim that "The fastest way to use migration assistant to move from and old Mac to new is to: create a CLONED backup of the old Mac..." which is untrue.It isn't just a matter of "What's fastest" but also "what's most cost effective AND "Fast Enough"
Paying $50 for a Thunderbolt cable to use once, is not cost effective.
Buying an external hard drive that you can then continue to use for backup or data, is cost effective.