[AnimalMuppet]

Bottom up may require a different learning ability. You read something, and you don't have a mental hook to hang it on yet, because you don't have any idea of the overall framework. So you have to be able to leave it hanging in midair for a while, until you learn enough of the higher-level structure to understand how it fits.

I used to be better at that when I was younger...

[aassddffasdf]

I think you have that backwards. Bottom up is about the composition of already understood pieces into more powerful ones (the utility of which is obvious due to solving limitations/ inconveniences inherent in the previous layer).