When row count is a fixed size, and row titles aren't specified in the field UI, table headers have one more column than data

It looks like the code expects that if the matrix field has a fixed number of rows specified, there should always be an extra empty header cell added to the table (i.e. an empty cell gets added to row 0, column 0). Unfortunately, this is only a safe assumption if row labels have been specified. If they haven't, the result is that the rendered table has one more column than the data rows actually have (since the labels don't render).

Additionally, if a fixed number of rows is specified for the matrix field, but not all rows have data, the extra rows look really ugly in the rendered table.