If they decide to play LI to mess you up and you do a 1-3-1 then you pretty much lose.
Not exactly. 1-3-1 offense puts a huge pressure on his PG. Against 1-3-1, his SG could have more assists than PG because of less pressure, but if his SG doesn't have good PA, than 1-3-1 succeeded.
And since his inside players receive less assists because of so much pressure on their PG, they don't make a lot of baskets unless they have good HA and DR to make their own shot.
That's the reason many times I play 3-2 against LI (1-3-1 is a bit dicey).