Bill had a csv file where in the spreadsheet he added a comment following a record. Autoplot could still plot a field by number, but he could no longer access the fields by the column header, because now there was an unnamed column at the right.
Autoplot should be willing to generate names for unnamed columns (fieldn), allowing the file to be used as before. This decouples what happens in one column from the use of another.
See https://github.com/autoplot/dev/blob/master/bugs/sf/2519/data.csv
In fact, it's worse than that, where it uses the comment as a column header.
This was resolved and will be in v2023a_7.