Looks odd to have ()2 rather than (2):
(2) would imply a list containing one element, 2.
The overloading of syntax was confusing some people, so the subscript notation was an attempt at disambiguation
()<subscript>2 implies a list containing 2 elements.
Okay thanks, just a bit different to the video so I assumed something was up!
I have the same issue with the screenshots in the docs, hard to keep these thing up-to-date