I don't see how this is any different. Where does the proposition, "do good directly, with your own mind and hands", lead? Should the first step not be "consider who is most in need"? Should the next stop not be "consider how best to help them"? And should the last step not be "help them in that way"?

It almost seems like you're arguing against examining the problem at all. What would the world look like if everybody just quit their jobs so they could do good "directly"? They'd realize pretty quick they needs planes and ships to move people and things, and farmers to grow food. Not to mention doctors and chemists to develop and administer medicine. If they were smart about it, they'd end up allocating their own time to the things they were best at, and then liquidate and donate any excess they produce.

If you just follow your heart, in the most basal sense, you will probably do some good and you will likely feel very good about it. Which is great for you, and good for those you help. There's nothing wrong with that. But that approach will never help those afflicted with malaria, because your heart doesn't know about them. Your head has to hear about them. And then your head has to tell you not to fly down there yourself, because if everybody did that then there'd be nobody back here running air traffic control or formulating medicine.