"In the small", it's easy to read code. This code computes this value, and writes it there, etc. The harder part is answering why it does what it does, which is harder for code someone else wrote. I think it is worthwhile expending this effort for code review, design review, or understanding a library. Not for code that I allegedly wrote. Especially weeks removed, loading code I wrote into "working memory" to fix issues or add features is much much easier than code I didn't write.