Caz, I think you're right. But the vernacular used by each CAD system is different to explain the same thing, so if you tell me your history I may be able to translate.
But yes, each part configuration, also known as family member, is defined within the master part but is populated, also known as saved as, its own file. That individual file is then used within assemblies. Why SE made parts their own files and assemblies (family of assemblies) have configurations, aka family members, stored within the one assembly file still confuses me. But that's the way it is.
Yes, Solidworks, Inventor, etc. etc. all store their family members as a configuration within one file. SE is unique in that regards when working with family of parts.
I got so fed up with family of parts that I ended up created a lot of my fasteners with a template. Change the dimensions, save as, change the dimension, save as. I get all the feature history, which is actually a minus in this case, but I still have all the same number of parts (less one if you count the master part file) and much less hassle with links.
--Scott