What's missing in the article for me is the ratio of candidates who scored well. I've learnt that you can have some excellent developers who get excluded which

What's missing in the article for me is the ratio of candidates who scored well. I've learnt that you can have some excellent developers who get excluded which half a day of training when they start can bring them up to speed. In my experience, interviewing is a costly process and being too particular can simply mean you don't find the right candidate. Companies which have a brand reputation that attracts talent can get away with this, but smaller more unknown companies sadly can't.