Its an old defensive programming habit I picked up from one of my professors way back when.  When dealing with signed values where negative numbers are illegal, it can be a good idea to do the more inclusive `< 1` since it catches overflow conditions as well.  It should never happen, but of course that is the nature of bugs.... sometimes unexpected things do occur.

Anyway, I can change it to `=== 0` or `!length` if that matches gaia style better.  (Although this particular line will probably go away when I remove the use of `delete`.)