I don't think that integration testing is sufficient (you will never catch every bug by writing tests - programming is too complex to expect any one coder to be perfect all the time). I'd also argue that writing too many integration tests can become a burden - having to change hundreds of tests when a site/app changes is tedious and time-consuming.

However, that doesn't mean that integration testing is useless. Writing a few tests to verify that mission-critical functions (like website registration) are working can save you when something goes wrong, and it's more efficient than doing manual regression testing every release.

Lastly, I really wish the author would give suggestions for what he considers to be a better approach to testing, beyond "integration testing sucks and is a scam".