HDD confusion
"an SSD can have more parallel read/write access streams inside it than a disk drive with six or seven read/write heads feeding a SAS or SATA interface"
Erm, Hard drives only use one head at a time. Trying to parallel them leads to all sorts of problems thanks to track alignment issues and they gave up trying decades ago. (it also means only one set of head drive logic is needed and switched between heads as required)
Biting the hand that feeds IT
