I wrote a blog on back-propagation to simplify the math with the hope that it would help folks like me who need to know whats happening under the hood. Feedback is welcome
I read through this . It starts off interestingly but once you start getting into the equations, there is no description of what any of the notations mean. if you want it to be widely understood (and may this is not the goal , its for a specific audience who understands notations without context), please define notations and symbols before you use them.