Earlier quoted context omitted.
The whole point of Deep Learning is that we don't want to describe math behind object recognition; it was the failed "classical" approach where people spent decades figuring out complex features which worked horribly. Deep Learning is actually pretty simple, well understood and parallelizable, and it's basically a billion-dimensional non-linear optimization. As optimization is infested with NP-hard problems, it's as…
Deep learning does not seem to abstract very well. Train on a data set then test with images that are simply upside down and the preformance can be significant. Feature extraction also works much better when you toss a lot of data and processing power behind it. So, a lot of progress is simply more data and computing power vs better approaches. Consider how poorly deep leaning works when using a single 286.
As much as architecture research gets denigrated these days, MLPs aren't what set off the revolution.