I just got around to trying this feature (been doing a pick from 2 patterns)
Code:
{series:switch("","00noseries"/{author_sort[0]}_authors/{authors}/{title}_{id}_{title}-{authors},{series[0]}-series/{series}/{series_index:0>2s}-{title}_{id}_{authors})}
When I save a series I get the second (else) part.
When the series is blank, the attached file (OPF part of the pair. Avoiding copyright issues

) name is generated (no folder path,either)
BTW,I tries without the quotes around 00noseries first.
did I miss something?
TNX