One possible dispute would be the "get ramen profitable first" point. There's a strong case to be made for taking money pre-revenue, before your metrics get harder to defend.
I would also argue that PPC can be used extremely early for A/B testing landing pages (and other testing uses), as well as, for customer acquisition if your product has the right market fit (cost per acquisition less than profit per sale).
Great point - small amount spent on A/B testing to identify wording, layout and messaging is super useful. Tim Ferris even used it to get the title of his book :-). When I wrote the post I was more thinking about actual user acquisition.
One possible dispute would be the "get ramen profitable first" point. There's a strong case to be made for taking money pre-revenue, before your metrics get harder to defend.