Why computation on private data matters for the public blockchains?

As some other blockchain projects working on secret smart contract puts it, blockchain without privacy is useless for businesses. while this view stands for critical data, any user data should yet be preserved and checkable an ideal world, that's one of the mottoes of the decentralized IT world.
We also choose to apply the KISS (Keep it Simple...) principle, by making our trusted validator nodes run the computation on the private data for you, the dApp one side and the user the other side. This way, we have certified results on certified data with no dApp making money out of data which transfer has not been approved. Simple, but working, and cheap also.