The article explicitly says that the author looked at the diffs; it distinguishes this from "sitting down and actually reading the code", which they didn't do. So when plastic041 says the author spent 7 months vibe coding "without ever looking at source code", it's not unreasonable for dewey to assume that "looking at source code", in this context, actually means something stronger and excludes just looking at the diffs.
The article explicitly says that the author looked at the diffs; it distinguishes this from "sitting down and actually reading the code", which they didn't do. So when plastic041 says the author spent 7 months vibe coding "without ever looking at source code", it's not unreasonable for dewey to assume that "looking at source code", in this context, actually means something stronger and excludes just looking at the diffs.