in reply to Kevan

Good question. I might need to think further on this - usually we get complaints if braille is NOT following along something someone wants read :)

You could press:
1) NVDA+control+t to specifically tether braille to the review cursor
2) NVDA+6 to set the review cursor NOT to follow focus
3) Read what you want.

You could then toggle where Braille is tethered before / after say all as needed to have it read other things?