Lets see.
SideB1 has lots of different hitboxes and each one has a variety of parameters which make each one a bit unique. Depending upon your opponents DI you can attempt to follow-up on a successful catch with SB1. I would think this is still to random to declare as being reliable. Especially, if you goal is to hit with the remaining hits of dancing blades. Depending upon how they DI, the character, and which hitbox you hit with you would need to use a different dancing blade follow-up to continue. If you hit with all three hits of dancing blade I believe you got lucky.
Otherwise, the first hit is incredibly useful by itself. If you want to use the remaining follow-ups its a bit of a gamble given its properties. Probably the primary use for SideB is its ability to be used on the ground when dashing away and turn around immediately. Just do not use it for cutting projectiles like Pills and Turnips. It just slices through it without interacting with the attack. However, its incredibly weak too and prone to CC therefore. Useful as an anti-air approach if timed well to prevent trading. Its a terrible move to trade with due to its lack of knockback. You get hit by a Fox nair and sent flying fox recovers almost instantly due to the weak attack.
Its doesn't combo into anything as far as I know on characters and percentage. But, its a very good "trap".