I wonder how far down this hole goes ...
From the car point of view I think almost everyone is tapering off the braking when starting to steer. It's extremely hard not to do it. So, I think, it's merely a matter of degree. And, if it's a matter of degree, then, presumably, people can get fairly good as playing in the range between none and too much. Do they leave anything in hand in case of the unforeseen? Well, isn't that what 'advanced' is all about?
Perhaps I'm a bit odd because, for my own pleasure and satisfaction, I like to have completed braking, and have changed gear, and be confidently back on the accelerator, before starting to steer
[*]. Again, I only drive, so I don't know how it is for riders, but by trying (and mostly failing) to do this, it's easy to see that pretty much everyone else doesn't even try and plays lip service to
Roadcrafts suggestion to have completed everything before the bend.
So, given my own predilection I get that others prefer to do it differently, and the thoughtful ones are trying to hone the skills of superior judgement with a smooth mid-bend transition off braking and onto the throttle, handling the weight shift with aplomb, while the thoughtless continue to sometimes make gaps in the scenery for cross-views.
[*] so that I can be ready to start chasing the limit point at the point it starts to run away