Intend Rocksteady Magic Cranks

 That theory checks out. Typically chain hangup's are from shifting under load, or grabbing too many gears in one throw. Otherwise it would be likely you have alignment, adjustment or chain issues that cause hang ups. What I'm getting at is, shifting while coasting there shouldn't be load on the chain. I'm late to the party, as always, just learned these cranks exist today. Cheers