I would have thought it is more common to have the RODI system tied into an intermediate ATO tank. Much less cycling on the RODI system this way and an extra safety buffer. Most systems I have seen actually have 2 storage units between the RODI filters and the DT's. The RODI unit fills a large container. The large container is used to supply the salt water container and the ATO container. The ATO container fills the DT.
I have no doubt that what you are describing will work and you look to have all the proper fail safes in place. Just not sure it has much benefit since most people with large systems also have large RODI and saltwater storage tanks.
