I see, but what I'm saying (in my previous post) is that theres no difference in the behaviour between:
(setq ss (ssget "_:L-I"))
and:
(or (setq ss (ssget "_:L-I"))
(setq ss (ssget "_:L"))
)
hence including the (setq ss (ssget "_:L")) and wrapping it within the or function is redundant.