Yep, I did exactly that this semester and it was very doable. In macroeconomics you can easily do well if you review the lecturers' notes thoroughly (I had Francisco and didn't attend a single lecture and did well) so it's all about understanding the concepts.

Lander is garbage and you'll have to put work, a lot of work, to do well, but it's possible. I'll tell you that overall, taking both of these classes together is very doable and you should be fine as long as you put the work in. However, I have a heavy math background and that is one of the reasons why I could do well in 337 with Lander, so be aware that if you are less confortable with math it will be harder. I recommend Linear Algebra as a math course that could help you a lot with 337.