Usually the break down of trips is
1 day ~8%
2 days~ 14%
3 days~67%
4 days ~ 12%
Commutable depends on where to/from. There might be 5 lines out of 400 that are truly commutable. Some will have some trips that are commutable but usually 1 maybe 2 out of the month.
the vastmajority 80% will only be commutable on one end.
then depending on where you commute from you might get a trip that isnt on either end or most likely get rerouted or delayed so much you miss it.
Sw is not a commuter friendly airline.