Of the five "obvious" words, two of them are used to say that something is not obvious and your last two examples are something entirely different. The uses her

Of the five "obvious" words, two of them are used to say that something is not obvious and your last two examples are something entirely different. The uses here seem quite reasonable. But these words should be helpful, not insulting! If it's not clear, as the author claims, then you've likely misunderstood something. No point pondering it for twenty minutes, better go back and reread the statement first. But of course they do get misused and there's not much more demoralizing than getting stuck on something 'obvious.'