Actually, I don't know what TDWTF article you might be referring to! (I drop in there occasionally, but not regularly, and I haven't seen this one.) Presumably this was somebody else having the //...\ problem in C++? The instance of that I was thinking of was from someone I know personally, who had written something along the lines of

    printf("complicated format string",
           arg1,
           arg2, // \
           arg3, //  } comment about these three
           arg4, // /
           arg5);

and got mysterious compiler warnings about the format string mismatching the parameters, which turned out to be because arg3 had been dropped on the floor. (Mystery eventually solved by using a later version of gcc, which helpfully gave a warning about the line-continued comment.)