House of Leaves is a good example of a book that experimented with formatting successfully. That said, it's pretty rare and it's important to understand why best practices exist, and practice working within those bounds, to be able to successfully break them. I think the odds of your friend pulling this off are low, but not impossible.

I'm assuming by "got published", you mean self-published. This would reduce my confidence in the experimentation being successful since there wasn't an additional layer of critique involved. I'm not saying that self-published authors haven't produced good work, because they absolutely have, just that there is value in an additional set of eyes in the decision making process.

I googled it and came up with a hit on the author and now I'm not sure this post is anything more than proof of concept for some marketing experiment.