Do some user testing with casual computer users (not even pure novices), and watch as you ask them to complete a two step task with a file (like, say, resize and then email). They can usually figure it out, but it takes them a long time and they become frustrated.
I've also observed this! But when I've seen people struggle with this kind of task, their problem has more often been the opposite of what you're talking about. They get files - that's easy! If the hierarchies aren't too deep, they can find their files too. But now what they struggle with in my experience is figuring out what program can achieve a given task - "should I open this in Preview? Can that do resizing? Or do I need to use iPhoto? Maybe none of the programs I have will work and I need to install something (oh no!)".
I think this is a deeper and more interesting problem. It's one that everyone suffers from - I was doing some work with STL files a while back - these are descriptions of 3D objects, and I had installed a bunch of different programs for working with STL files. The problem I had was remembering which program could do which things!
The solution to this problem is not to lock things down so tightly that there is a 1-to-1 correspondence between types of objects (photos, videos, etc) and the "blessed" programs that are allowed to access the databases that those objects live in.
I've also observed this! But when I've seen people struggle with this kind of task, their problem has more often been the opposite of what you're talking about. They get files - that's easy! If the hierarchies aren't too deep, they can find their files too. But now what they struggle with in my experience is figuring out what program can achieve a given task - "should I open this in Preview? Can that do resizing? Or do I need to use iPhoto? Maybe none of the programs I have will work and I need to install something (oh no!)".
I think this is a deeper and more interesting problem. It's one that everyone suffers from - I was doing some work with STL files a while back - these are descriptions of 3D objects, and I had installed a bunch of different programs for working with STL files. The problem I had was remembering which program could do which things!
The solution to this problem is not to lock things down so tightly that there is a 1-to-1 correspondence between types of objects (photos, videos, etc) and the "blessed" programs that are allowed to access the databases that those objects live in.