Its extremely hard to definitively define best practises. You'd be surprised how many practitioners still argue for what look like clearly outdated ways of doing things. There's also the argument that in some people's hands an outdated way of doing things is safer than a newer (better?) way of doing things in their hands. eg. A surgeon who has been practising for 30 years but only recently learned to use a laparoscope.

I doubt ambulance chasers do anything other than muddy the waters and enrich themselves at the healthcare systems expense.