It took a lott of work, but we finally have the right rankings for operator[] to work as intended with as minimal room for screwups as possible.
This should enable operator[] to work in all cases that it is to be expected, thanks to a lot of explicit conversions and some basic overload resolution ranking tricks (e.g., making some conversions a template).
We also need to remember that GCC expects `. template (function name)` in generic code, as it can parse things in a really dumb and silly manner.