Then, there are tools to analyze and inspect those logs. You can presumably replay a frame, and step through each GL call and inspect the data it is sending. I haven't tried building this yet, but it looks like it includes a tool to replay the GL calls, and some kind of interactive GUI.
Many C++ devs have a different idea on what idiomatic C++ should look like. C++11 really shakes things up as well.
There's no reason a "using namespace std;" is bad, as long as it isn't in the header. If it's in the header file, every file that includes that header will have it's namespace polluted with std declarations, and this leads to a big nasty chain of potential name conflicts (one header file includes another and so on and so forth).