I don't think it's accurate to say it's a different point, but it's a weaker version. And I don't feel that the GraphChi folks have any explaining to do, as I w

I don't think it's accurate to say it's a different point, but it's a weaker version. And I don't feel that the GraphChi folks have any explaining to do, as I would expect that using a more general framework to solve a problem will have some performance penalty over an expert hand-coding a solution. What that performance penalty would buy us (hopefully) is it's quicker to write the application, and perhaps easier to port elsewhere. But, I'm also not an expert in graph algorithms, so it's difficult for me to evaluate how much domain knowledge you needed to implement yours.