Why the huge variation in interventions for the same inputs?
If the same software was giving different outputs for the same inputs in 2 different locations, everyone here would see that as a concern to be addressed.
A software analogy would be: if a client asks for a simple website with a shopping cart and a newsletter, and you ask 10 programmers, you're almost guaranteed to get 10 different platforms (different CMS, different language like PHP vs Ruby vs .net)
It's kind of the same thing with dentists: a good surgeon will tend to lean towards surgery, and there are usually at least 2-3 different ways of solving a particular problem
If the same software was giving different outputs for the same inputs in 2 different locations, everyone here would see that as a concern to be addressed.