You elided the part where TFA claims you can't test "unconventional email formats" via test orders. The full quote is:
Shopify doesn’t provide a way to test unconventional email formats without actually placing real orders, so I did my customary dance of order-refund, order-refund, order-refund. My credit card is going to get locked one of these days.
The person who wrote the above knows a lot about Shopify, so if you're going to contradict them, it'd be nice to point to some evidence as to why you think they're wrong.
Shopify doesn’t provide a way to test unconventional email formats without actually placing real orders, so I did my customary dance of order-refund, order-refund, order-refund. My credit card is going to get locked one of these days.
The person who wrote the above knows a lot about Shopify, so if you're going to contradict them, it'd be nice to point to some evidence as to why you think they're wrong.