Actually, ISR was primarily intended for SSD-HDD communication, where the SSD acts as a giant memory, for frequently accessed data. When time permits that data is then transferred back to the HDD, so any programs on the HDD can use the SSD as a cache. The combination of an SSD and a HDD is a Hybrid Drive which Seagate makes and is attempting to eliminate lag times for read/write to HDD from cache without having to use the SATA pathways.
So even though the SSD is the boot.. primary.. main drive, not all op's programs will be stored there and once accessed will be able to take any and all advantage of the SSD that it has to offer. That said, on a B85 board that does not support ISR, the OP will have an SSD for boot drive, and a HDD for storage, and no communication between, so only programs on the SSD will have SSD read/write times vrs HDD read/write times.
Smart Storage was something else entirely, and was designed for 60GB and below SSDs that were not the primary drive, but could be used as a cache for windows and other programs to temporarily store the entire data of the program, while used, and then written back to the HDD after close. This was back when 6-12GB SSD's were common, and Intel got caught with their pants down not expecting the meteoric rise in GB capability, which is why they capped ISS at 60GB