I agree with the author for the most part. An exception to this rule is that in terms of front-end (or end-to-end) testing, if an application is deterministic,

I agree with the author for the most part. An exception to this rule is that in terms of front-end (or end-to-end) testing, if an application is deterministic, you most certainly don't need to write any code to create tests for it. You can record actions and snapshots and replay the actions and compare snapshots. There can often be more to it than that (like filtering dynamic elements/attributes and pattern matching), but for the most part, this approach works quite well.