The -1 switch (that’s the numeral one, not the letter ell) effectively cancels out most of the point of PolyShell by limiting the number of child sessions to one. Why would anyone want to do such a silly thing? One not-too-farfetched reason might be that you like the way PolyShell intercepts SEND.LIT messages without overwriting the current screen comments, but you don’t want certain single-tasking users to get confused by launching more than one session.