Can you please answer me one thing, in your words, what are these packages you are talking about?
To oversimplify it:
Games for HDDs don't load single texture/object files, they load stuff in compressed containers that contains many objects etc, because HDDs can't handle many small reads so good. So you create packages to load as much as needed (and more). Else the HDDs bandwidth would drastically suffer.
BTW, this is a fact and no speculation.
So if a BC game runs on the new hardware the SSD helps with massive bandwidth and the CPU helps with faster decompression. This is the brute forcing you know from running the games on pc.
If the game is optimized for a SSD, it will only load the stuff that is actually needed, compressed in a Form, the hardware acceleration can decompress. This is way faster.
Whenever you see a load screen in current games, most of the time the game just tries to copy the packets into memory and decompress them for later use.