I disagree with the bolded bit. Shield performances are one part of the equation, but selectors have to be better than just saying "this guy is making the most runs/taking the most wickets right now, let's pick him". There are heaps of other factors. I think Marcus Harris, for instance, has proven to be below test standard - he could score 2,000 runs in a Shield season and I still wouldn't pick him. There are times when you go for a younger player with potential ahead of a seasoned pro. Renshaw was in the recent squad and will likely go to NZ because he can bat anywhere in the top six.I get the argument for Renshaw's A form and age, but ultimately, we should still prioritise Shield form. The majority of our games are played here in Oz, we shouldn't be picking teams based on how they perform in one country, unless they want to go horses for courses (which I don't necessarily have a problem with, picking in Oz and Renshaw in England, for example, makes some sense).
As a Western Australian, of course, I'd like to see Bancroft play for Australia. But there are plenty of reasons that explain why he's not.