It is an interesting point, but the performance improvements he desires can be accomplished with encapsulation by employing polymorphic types (storing a header of type H that the Person type can't operate on because it only knows it is an H but the container collection can) but of course this binds the instances (e.g. of Person) to the type of H they were constructed with so they can't be added to other types of containers that require another type for H. But his C solution also makes this conflation.

The reason to prefer C over C++ is that C has a smaller surface area of base concepts whereas C++ has everything and the kitchen sink in its 1500 page manual.

When it comes to performance, a skilled C programmer can beat an average C++ programmer who utilizes the STL. So jl777 wants to understand the algorithms well enough so that he can create a C implementation. This seems to be a worthwhile activity as it will make the Zcash PoW algorithm accessible to C programmers who hate C++ of which there are probably many.

I would bet that if you can write down the algorithms in a simple pseudo code which he can easily translate to C, then I bet he'd probably pay you the bounty.