Quote Originally Posted by Silver Rusher
That's what I think, it's only easy for fluent or even native speakers of the language to tell the difference between two accents. I for example couldn't tell the difference between Spanish spoken by a Spanish person and Spanish spoken by a Mexican (except for the pronunciation of z's and c's, which is like a th sound in Castilian but not in Latin American).
I'd say it's sometimes difficult to tell accents apart even if one is a native speaker, Aussie/New Zealander for example.

If I heard them together, I imagine I could tell them apart and tell which one was which (getting them to say fish and chips would be a dead give away). However, if I heard them individually I suspect I'd have more trouble. Likewise with various t'northern accents (I'm very much a 'home counties' southerner): I doubt I could tell the difference between a Lancashire and a Yorkshire accent unless they were together, and even then I suspect I'd have difficulty...