Very clear, concise, sharp goals that are actionable and measurable.
Programmers can decently estimate what they can do in a day. I know I struggle to estimate for longer projects.
Is there any concern of burnout with maintaining such a pace?
What happens if something slips the 2-day goal?
How do you deal with something that requires more than two days? Split it up over multiple sprints? What if you can't?
While I agree, focusing on getting something shipped every 2 days isn't a huge pace. It means you iterate tightly and goals are understood to be scoped to only 2 days of work.
If something slips the 2-day goal, it's debt, and it's expected to be nailed first-thing in the next sprint. It's a flexible system.
For bigger projects, you _have_ to be able to split them up. I honestly can't think of a single project where you couldn't break it down into constituent parts in which you could iterate through several sprints to finish it.
If you're doing research-based work, I'll admit this probably isn't the best approach. However, from a business and personal productivity perspective, it's working very well.